Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
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 | |
55aa4f58 CL |
13 | * the request struct, and calls xprt_transmit(). |
14 | * - xprt_transmit sends the message and installs the caller on the | |
15 | * transport's wait list. At the same time, it installs a timer that | |
1da177e4 LT |
16 | * is run after the packet's timeout has expired. |
17 | * - When a packet arrives, the data_ready handler walks the list of | |
55aa4f58 | 18 | * pending requests for that transport. If a matching XID is found, the |
1da177e4 LT |
19 | * caller is woken up, and the timer removed. |
20 | * - When no reply arrives within the timeout interval, the timer is | |
21 | * fired by the kernel and runs xprt_timer(). It either adjusts the | |
22 | * timeout values (minor timeout) or wakes up the caller with a status | |
23 | * of -ETIMEDOUT. | |
24 | * - When the caller receives a notification from RPC that a reply arrived, | |
25 | * it should release the RPC slot, and process the reply. | |
26 | * If the call timed out, it may choose to retry the operation by | |
27 | * adjusting the initial timeout value, and simply calling rpc_call | |
28 | * again. | |
29 | * | |
30 | * Support for async RPC is done through a set of RPC-specific scheduling | |
31 | * primitives that `transparently' work for processes as well as async | |
32 | * tasks that rely on callbacks. | |
33 | * | |
34 | * Copyright (C) 1995-1997, Olaf Kirch <okir@monad.swb.de> | |
55aa4f58 CL |
35 | * |
36 | * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> | |
1da177e4 LT |
37 | */ |
38 | ||
a246b010 CL |
39 | #include <linux/module.h> |
40 | ||
1da177e4 | 41 | #include <linux/types.h> |
a246b010 | 42 | #include <linux/interrupt.h> |
1da177e4 | 43 | #include <linux/workqueue.h> |
bf3fcf89 | 44 | #include <linux/net.h> |
1da177e4 | 45 | |
a246b010 | 46 | #include <linux/sunrpc/clnt.h> |
11c556b3 | 47 | #include <linux/sunrpc/metrics.h> |
1da177e4 LT |
48 | |
49 | /* | |
50 | * Local variables | |
51 | */ | |
52 | ||
53 | #ifdef RPC_DEBUG | |
1da177e4 LT |
54 | # define RPCDBG_FACILITY RPCDBG_XPRT |
55 | #endif | |
56 | ||
1da177e4 LT |
57 | /* |
58 | * Local functions | |
59 | */ | |
60 | static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); | |
61 | static inline void do_xprt_reserve(struct rpc_task *); | |
1da177e4 | 62 | static void xprt_connect_status(struct rpc_task *task); |
1da177e4 LT |
63 | static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
64 | ||
5ba03e82 | 65 | static DEFINE_SPINLOCK(xprt_list_lock); |
81c098af TT |
66 | static LIST_HEAD(xprt_list); |
67 | ||
555ee3af CL |
68 | /* |
69 | * The transport code maintains an estimate on the maximum number of out- | |
70 | * standing RPC requests, using a smoothed version of the congestion | |
71 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
72 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
73 | * halved; otherwise, it is incremented by 1/cwnd when | |
74 | * | |
75 | * - a reply is received and | |
76 | * - a full number of requests are outstanding and | |
77 | * - the congestion window hasn't been updated recently. | |
78 | */ | |
79 | #define RPC_CWNDSHIFT (8U) | |
80 | #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) | |
81 | #define RPC_INITCWND RPC_CWNDSCALE | |
82 | #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) | |
83 | ||
84 | #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) | |
1da177e4 | 85 | |
81c098af TT |
86 | /** |
87 | * xprt_register_transport - register a transport implementation | |
88 | * @transport: transport to register | |
89 | * | |
90 | * If a transport implementation is loaded as a kernel module, it can | |
91 | * call this interface to make itself known to the RPC client. | |
92 | * | |
93 | * Returns: | |
94 | * 0: transport successfully registered | |
95 | * -EEXIST: transport already registered | |
96 | * -EINVAL: transport module being unloaded | |
97 | */ | |
98 | int xprt_register_transport(struct xprt_class *transport) | |
99 | { | |
100 | struct xprt_class *t; | |
101 | int result; | |
102 | ||
103 | result = -EEXIST; | |
104 | spin_lock(&xprt_list_lock); | |
105 | list_for_each_entry(t, &xprt_list, list) { | |
106 | /* don't register the same transport class twice */ | |
4fa016eb | 107 | if (t->ident == transport->ident) |
81c098af TT |
108 | goto out; |
109 | } | |
110 | ||
c9f6cde6 DL |
111 | list_add_tail(&transport->list, &xprt_list); |
112 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
113 | transport->name); | |
114 | result = 0; | |
81c098af TT |
115 | |
116 | out: | |
117 | spin_unlock(&xprt_list_lock); | |
118 | return result; | |
119 | } | |
120 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
121 | ||
122 | /** | |
123 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 124 | * @transport: transport to unregister |
81c098af TT |
125 | * |
126 | * Returns: | |
127 | * 0: transport successfully unregistered | |
128 | * -ENOENT: transport never registered | |
129 | */ | |
130 | int xprt_unregister_transport(struct xprt_class *transport) | |
131 | { | |
132 | struct xprt_class *t; | |
133 | int result; | |
134 | ||
135 | result = 0; | |
136 | spin_lock(&xprt_list_lock); | |
137 | list_for_each_entry(t, &xprt_list, list) { | |
138 | if (t == transport) { | |
139 | printk(KERN_INFO | |
140 | "RPC: Unregistered %s transport module.\n", | |
141 | transport->name); | |
142 | list_del_init(&transport->list); | |
81c098af TT |
143 | goto out; |
144 | } | |
145 | } | |
146 | result = -ENOENT; | |
147 | ||
148 | out: | |
149 | spin_unlock(&xprt_list_lock); | |
150 | return result; | |
151 | } | |
152 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
153 | ||
441e3e24 TT |
154 | /** |
155 | * xprt_load_transport - load a transport implementation | |
156 | * @transport_name: transport to load | |
157 | * | |
158 | * Returns: | |
159 | * 0: transport successfully loaded | |
160 | * -ENOENT: transport module not available | |
161 | */ | |
162 | int xprt_load_transport(const char *transport_name) | |
163 | { | |
164 | struct xprt_class *t; | |
165 | char module_name[sizeof t->name + 5]; | |
166 | int result; | |
167 | ||
168 | result = 0; | |
169 | spin_lock(&xprt_list_lock); | |
170 | list_for_each_entry(t, &xprt_list, list) { | |
171 | if (strcmp(t->name, transport_name) == 0) { | |
172 | spin_unlock(&xprt_list_lock); | |
173 | goto out; | |
174 | } | |
175 | } | |
176 | spin_unlock(&xprt_list_lock); | |
177 | strcpy(module_name, "xprt"); | |
178 | strncat(module_name, transport_name, sizeof t->name); | |
179 | result = request_module(module_name); | |
180 | out: | |
181 | return result; | |
182 | } | |
183 | EXPORT_SYMBOL_GPL(xprt_load_transport); | |
184 | ||
12a80469 CL |
185 | /** |
186 | * xprt_reserve_xprt - serialize write access to transports | |
187 | * @task: task that is requesting access to the transport | |
188 | * | |
189 | * This prevents mixing the payload of separate requests, and prevents | |
190 | * transport connects from colliding with writes. No congestion control | |
191 | * is provided. | |
192 | */ | |
193 | int xprt_reserve_xprt(struct rpc_task *task) | |
194 | { | |
195 | struct rpc_xprt *xprt = task->tk_xprt; | |
196 | struct rpc_rqst *req = task->tk_rqstp; | |
197 | ||
198 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
199 | if (task == xprt->snd_task) | |
200 | return 1; | |
201 | if (task == NULL) | |
202 | return 0; | |
203 | goto out_sleep; | |
204 | } | |
205 | xprt->snd_task = task; | |
206 | if (req) { | |
207 | req->rq_bytes_sent = 0; | |
208 | req->rq_ntrans++; | |
209 | } | |
210 | return 1; | |
211 | ||
212 | out_sleep: | |
46121cf7 | 213 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
214 | task->tk_pid, xprt); |
215 | task->tk_timeout = 0; | |
216 | task->tk_status = -EAGAIN; | |
217 | if (req && req->rq_ntrans) | |
5d00837b | 218 | rpc_sleep_on(&xprt->resend, task, NULL); |
12a80469 | 219 | else |
5d00837b | 220 | rpc_sleep_on(&xprt->sending, task, NULL); |
12a80469 CL |
221 | return 0; |
222 | } | |
12444809 | 223 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 224 | |
632e3bdc TM |
225 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
226 | { | |
227 | xprt->snd_task = NULL; | |
228 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { | |
229 | smp_mb__before_clear_bit(); | |
230 | clear_bit(XPRT_LOCKED, &xprt->state); | |
231 | smp_mb__after_clear_bit(); | |
232 | } else | |
c1384c9c | 233 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
234 | } |
235 | ||
1da177e4 | 236 | /* |
12a80469 CL |
237 | * xprt_reserve_xprt_cong - serialize write access to transports |
238 | * @task: task that is requesting access to the transport | |
239 | * | |
240 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
241 | * integrated into the decision of whether a request is allowed to be | |
242 | * woken up and given access to the transport. | |
1da177e4 | 243 | */ |
12a80469 | 244 | int xprt_reserve_xprt_cong(struct rpc_task *task) |
1da177e4 | 245 | { |
12a80469 | 246 | struct rpc_xprt *xprt = task->tk_xprt; |
1da177e4 LT |
247 | struct rpc_rqst *req = task->tk_rqstp; |
248 | ||
2226feb6 | 249 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
250 | if (task == xprt->snd_task) |
251 | return 1; | |
1da177e4 LT |
252 | goto out_sleep; |
253 | } | |
12a80469 | 254 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
255 | xprt->snd_task = task; |
256 | if (req) { | |
257 | req->rq_bytes_sent = 0; | |
258 | req->rq_ntrans++; | |
259 | } | |
260 | return 1; | |
261 | } | |
632e3bdc | 262 | xprt_clear_locked(xprt); |
1da177e4 | 263 | out_sleep: |
46121cf7 | 264 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
265 | task->tk_timeout = 0; |
266 | task->tk_status = -EAGAIN; | |
267 | if (req && req->rq_ntrans) | |
5d00837b | 268 | rpc_sleep_on(&xprt->resend, task, NULL); |
1da177e4 | 269 | else |
5d00837b | 270 | rpc_sleep_on(&xprt->sending, task, NULL); |
1da177e4 LT |
271 | return 0; |
272 | } | |
12444809 | 273 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 274 | |
12a80469 | 275 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
276 | { |
277 | int retval; | |
278 | ||
4a0f8c04 | 279 | spin_lock_bh(&xprt->transport_lock); |
12a80469 | 280 | retval = xprt->ops->reserve_xprt(task); |
4a0f8c04 | 281 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
282 | return retval; |
283 | } | |
284 | ||
12a80469 | 285 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
49e9a890 CL |
286 | { |
287 | struct rpc_task *task; | |
288 | struct rpc_rqst *req; | |
289 | ||
290 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
291 | return; | |
292 | ||
293 | task = rpc_wake_up_next(&xprt->resend); | |
294 | if (!task) { | |
295 | task = rpc_wake_up_next(&xprt->sending); | |
296 | if (!task) | |
297 | goto out_unlock; | |
298 | } | |
299 | ||
300 | req = task->tk_rqstp; | |
301 | xprt->snd_task = task; | |
302 | if (req) { | |
303 | req->rq_bytes_sent = 0; | |
304 | req->rq_ntrans++; | |
305 | } | |
306 | return; | |
307 | ||
308 | out_unlock: | |
632e3bdc | 309 | xprt_clear_locked(xprt); |
49e9a890 CL |
310 | } |
311 | ||
312 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
1da177e4 LT |
313 | { |
314 | struct rpc_task *task; | |
315 | ||
2226feb6 | 316 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 317 | return; |
49e9a890 | 318 | if (RPCXPRT_CONGESTED(xprt)) |
1da177e4 LT |
319 | goto out_unlock; |
320 | task = rpc_wake_up_next(&xprt->resend); | |
321 | if (!task) { | |
322 | task = rpc_wake_up_next(&xprt->sending); | |
323 | if (!task) | |
324 | goto out_unlock; | |
325 | } | |
49e9a890 | 326 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
327 | struct rpc_rqst *req = task->tk_rqstp; |
328 | xprt->snd_task = task; | |
329 | if (req) { | |
330 | req->rq_bytes_sent = 0; | |
331 | req->rq_ntrans++; | |
332 | } | |
333 | return; | |
334 | } | |
335 | out_unlock: | |
632e3bdc | 336 | xprt_clear_locked(xprt); |
1da177e4 LT |
337 | } |
338 | ||
49e9a890 CL |
339 | /** |
340 | * xprt_release_xprt - allow other requests to use a transport | |
341 | * @xprt: transport with other tasks potentially waiting | |
342 | * @task: task that is releasing access to the transport | |
343 | * | |
344 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 345 | */ |
49e9a890 | 346 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
347 | { |
348 | if (xprt->snd_task == task) { | |
632e3bdc | 349 | xprt_clear_locked(xprt); |
1da177e4 LT |
350 | __xprt_lock_write_next(xprt); |
351 | } | |
352 | } | |
12444809 | 353 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 354 | |
49e9a890 CL |
355 | /** |
356 | * xprt_release_xprt_cong - allow other requests to use a transport | |
357 | * @xprt: transport with other tasks potentially waiting | |
358 | * @task: task that is releasing access to the transport | |
359 | * | |
360 | * Note that "task" can be NULL. Another task is awoken to use the | |
361 | * transport if the transport's congestion window allows it. | |
362 | */ | |
363 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
364 | { | |
365 | if (xprt->snd_task == task) { | |
632e3bdc | 366 | xprt_clear_locked(xprt); |
49e9a890 CL |
367 | __xprt_lock_write_next_cong(xprt); |
368 | } | |
369 | } | |
12444809 | 370 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
371 | |
372 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 373 | { |
4a0f8c04 | 374 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 375 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 376 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
377 | } |
378 | ||
1da177e4 LT |
379 | /* |
380 | * Van Jacobson congestion avoidance. Check if the congestion window | |
381 | * overflowed. Put the task to sleep if this is the case. | |
382 | */ | |
383 | static int | |
384 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
385 | { | |
386 | struct rpc_rqst *req = task->tk_rqstp; | |
387 | ||
388 | if (req->rq_cong) | |
389 | return 1; | |
46121cf7 | 390 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
391 | task->tk_pid, xprt->cong, xprt->cwnd); |
392 | if (RPCXPRT_CONGESTED(xprt)) | |
393 | return 0; | |
394 | req->rq_cong = 1; | |
395 | xprt->cong += RPC_CWNDSCALE; | |
396 | return 1; | |
397 | } | |
398 | ||
399 | /* | |
400 | * Adjust the congestion window, and wake up the next task | |
401 | * that has been sleeping due to congestion | |
402 | */ | |
403 | static void | |
404 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
405 | { | |
406 | if (!req->rq_cong) | |
407 | return; | |
408 | req->rq_cong = 0; | |
409 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 410 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
411 | } |
412 | ||
a58dd398 CL |
413 | /** |
414 | * xprt_release_rqst_cong - housekeeping when request is complete | |
415 | * @task: RPC request that recently completed | |
416 | * | |
417 | * Useful for transports that require congestion control. | |
418 | */ | |
419 | void xprt_release_rqst_cong(struct rpc_task *task) | |
420 | { | |
421 | __xprt_put_cong(task->tk_xprt, task->tk_rqstp); | |
422 | } | |
12444809 | 423 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 424 | |
46c0ee8b CL |
425 | /** |
426 | * xprt_adjust_cwnd - adjust transport congestion window | |
427 | * @task: recently completed RPC request used to adjust window | |
428 | * @result: result code of completed RPC request | |
429 | * | |
1da177e4 LT |
430 | * We use a time-smoothed congestion estimator to avoid heavy oscillation. |
431 | */ | |
46c0ee8b | 432 | void xprt_adjust_cwnd(struct rpc_task *task, int result) |
1da177e4 | 433 | { |
46c0ee8b CL |
434 | struct rpc_rqst *req = task->tk_rqstp; |
435 | struct rpc_xprt *xprt = task->tk_xprt; | |
436 | unsigned long cwnd = xprt->cwnd; | |
1da177e4 | 437 | |
1da177e4 LT |
438 | if (result >= 0 && cwnd <= xprt->cong) { |
439 | /* The (cwnd >> 1) term makes sure | |
440 | * the result gets rounded properly. */ | |
441 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
442 | if (cwnd > RPC_MAXCWND(xprt)) | |
443 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 444 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
445 | } else if (result == -ETIMEDOUT) { |
446 | cwnd >>= 1; | |
447 | if (cwnd < RPC_CWNDSCALE) | |
448 | cwnd = RPC_CWNDSCALE; | |
449 | } | |
46121cf7 | 450 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
451 | xprt->cong, xprt->cwnd, cwnd); |
452 | xprt->cwnd = cwnd; | |
46c0ee8b | 453 | __xprt_put_cong(xprt, req); |
1da177e4 | 454 | } |
12444809 | 455 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 456 | |
44fbac22 CL |
457 | /** |
458 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
459 | * @xprt: transport with waiting tasks | |
460 | * @status: result code to plant in each task before waking it | |
461 | * | |
462 | */ | |
463 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
464 | { | |
465 | if (status < 0) | |
466 | rpc_wake_up_status(&xprt->pending, status); | |
467 | else | |
468 | rpc_wake_up(&xprt->pending); | |
469 | } | |
12444809 | 470 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 471 | |
c7b2cae8 CL |
472 | /** |
473 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
474 | * @task: task to be put to sleep | |
0b80ae42 | 475 | * @action: function pointer to be executed after wait |
c7b2cae8 | 476 | */ |
b6ddf64f | 477 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
478 | { |
479 | struct rpc_rqst *req = task->tk_rqstp; | |
480 | struct rpc_xprt *xprt = req->rq_xprt; | |
481 | ||
482 | task->tk_timeout = req->rq_timeout; | |
b6ddf64f | 483 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 484 | } |
12444809 | 485 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
486 | |
487 | /** | |
488 | * xprt_write_space - wake the task waiting for transport output buffer space | |
489 | * @xprt: transport with waiting tasks | |
490 | * | |
491 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
492 | */ | |
493 | void xprt_write_space(struct rpc_xprt *xprt) | |
494 | { | |
495 | if (unlikely(xprt->shutdown)) | |
496 | return; | |
497 | ||
498 | spin_lock_bh(&xprt->transport_lock); | |
499 | if (xprt->snd_task) { | |
46121cf7 CL |
500 | dprintk("RPC: write space: waking waiting task on " |
501 | "xprt %p\n", xprt); | |
fda13939 | 502 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
503 | } |
504 | spin_unlock_bh(&xprt->transport_lock); | |
505 | } | |
12444809 | 506 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 507 | |
fe3aca29 CL |
508 | /** |
509 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
510 | * @task: task whose timeout is to be set | |
511 | * | |
512 | * Set a request's retransmit timeout based on the transport's | |
513 | * default timeout parameters. Used by transports that don't adjust | |
514 | * the retransmit timeout based on round-trip time estimation. | |
515 | */ | |
516 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
517 | { | |
518 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
519 | } | |
12444809 | 520 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 CL |
521 | |
522 | /* | |
523 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout | |
524 | * @task: task whose timeout is to be set | |
cca5172a | 525 | * |
fe3aca29 CL |
526 | * Set a request's retransmit timeout using the RTT estimator. |
527 | */ | |
528 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
529 | { | |
530 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
531 | struct rpc_clnt *clnt = task->tk_client; |
532 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 533 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 534 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
535 | |
536 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
537 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
538 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
539 | task->tk_timeout = max_timeout; | |
540 | } | |
12444809 | 541 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 542 | |
1da177e4 LT |
543 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
544 | { | |
ba7392bb | 545 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
546 | |
547 | req->rq_majortimeo = req->rq_timeout; | |
548 | if (to->to_exponential) | |
549 | req->rq_majortimeo <<= to->to_retries; | |
550 | else | |
551 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
552 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
553 | req->rq_majortimeo = to->to_maxval; | |
554 | req->rq_majortimeo += jiffies; | |
555 | } | |
556 | ||
9903cd1c CL |
557 | /** |
558 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
559 | * @req: RPC request containing parameters to use for the adjustment | |
560 | * | |
1da177e4 LT |
561 | */ |
562 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
563 | { | |
564 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 565 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
566 | int status = 0; |
567 | ||
568 | if (time_before(jiffies, req->rq_majortimeo)) { | |
569 | if (to->to_exponential) | |
570 | req->rq_timeout <<= 1; | |
571 | else | |
572 | req->rq_timeout += to->to_increment; | |
573 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
574 | req->rq_timeout = to->to_maxval; | |
575 | req->rq_retries++; | |
1da177e4 LT |
576 | } else { |
577 | req->rq_timeout = to->to_initval; | |
578 | req->rq_retries = 0; | |
579 | xprt_reset_majortimeo(req); | |
580 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 581 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 582 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 583 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
584 | status = -ETIMEDOUT; |
585 | } | |
586 | ||
587 | if (req->rq_timeout == 0) { | |
588 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
589 | req->rq_timeout = 5 * HZ; | |
590 | } | |
591 | return status; | |
592 | } | |
593 | ||
65f27f38 | 594 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 595 | { |
65f27f38 DH |
596 | struct rpc_xprt *xprt = |
597 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 598 | |
a246b010 | 599 | xprt->ops->close(xprt); |
66af1e55 | 600 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
1da177e4 LT |
601 | xprt_release_write(xprt, NULL); |
602 | } | |
603 | ||
9903cd1c | 604 | /** |
62da3b24 | 605 | * xprt_disconnect_done - mark a transport as disconnected |
9903cd1c CL |
606 | * @xprt: transport to flag for disconnect |
607 | * | |
1da177e4 | 608 | */ |
62da3b24 | 609 | void xprt_disconnect_done(struct rpc_xprt *xprt) |
1da177e4 | 610 | { |
46121cf7 | 611 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 612 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 613 | xprt_clear_connected(xprt); |
2a491991 | 614 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
4a0f8c04 | 615 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 616 | } |
62da3b24 | 617 | EXPORT_SYMBOL_GPL(xprt_disconnect_done); |
1da177e4 | 618 | |
66af1e55 TM |
619 | /** |
620 | * xprt_force_disconnect - force a transport to disconnect | |
621 | * @xprt: transport to disconnect | |
622 | * | |
623 | */ | |
624 | void xprt_force_disconnect(struct rpc_xprt *xprt) | |
625 | { | |
626 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
627 | spin_lock_bh(&xprt->transport_lock); | |
628 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
629 | /* Try to schedule an autoclose RPC call */ | |
630 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
631 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 632 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
66af1e55 TM |
633 | spin_unlock_bh(&xprt->transport_lock); |
634 | } | |
66af1e55 | 635 | |
7c1d71cf TM |
636 | /** |
637 | * xprt_conditional_disconnect - force a transport to disconnect | |
638 | * @xprt: transport to disconnect | |
639 | * @cookie: 'connection cookie' | |
640 | * | |
641 | * This attempts to break the connection if and only if 'cookie' matches | |
642 | * the current transport 'connection cookie'. It ensures that we don't | |
643 | * try to break the connection more than once when we need to retransmit | |
644 | * a batch of RPC requests. | |
645 | * | |
646 | */ | |
647 | void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) | |
648 | { | |
649 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
650 | spin_lock_bh(&xprt->transport_lock); | |
651 | if (cookie != xprt->connect_cookie) | |
652 | goto out; | |
653 | if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) | |
654 | goto out; | |
655 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
656 | /* Try to schedule an autoclose RPC call */ | |
657 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
658 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 659 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
7c1d71cf TM |
660 | out: |
661 | spin_unlock_bh(&xprt->transport_lock); | |
662 | } | |
663 | ||
1da177e4 LT |
664 | static void |
665 | xprt_init_autodisconnect(unsigned long data) | |
666 | { | |
667 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
668 | ||
4a0f8c04 | 669 | spin_lock(&xprt->transport_lock); |
1da177e4 LT |
670 | if (!list_empty(&xprt->recv) || xprt->shutdown) |
671 | goto out_abort; | |
2226feb6 | 672 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 673 | goto out_abort; |
4a0f8c04 | 674 | spin_unlock(&xprt->transport_lock); |
2226feb6 | 675 | if (xprt_connecting(xprt)) |
1da177e4 LT |
676 | xprt_release_write(xprt, NULL); |
677 | else | |
c1384c9c | 678 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
1da177e4 LT |
679 | return; |
680 | out_abort: | |
4a0f8c04 | 681 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
682 | } |
683 | ||
9903cd1c CL |
684 | /** |
685 | * xprt_connect - schedule a transport connect operation | |
686 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
687 | * |
688 | */ | |
689 | void xprt_connect(struct rpc_task *task) | |
690 | { | |
691 | struct rpc_xprt *xprt = task->tk_xprt; | |
692 | ||
46121cf7 | 693 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
694 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
695 | ||
ec739ef0 | 696 | if (!xprt_bound(xprt)) { |
01d37c42 | 697 | task->tk_status = -EAGAIN; |
1da177e4 LT |
698 | return; |
699 | } | |
700 | if (!xprt_lock_write(xprt, task)) | |
701 | return; | |
702 | if (xprt_connected(xprt)) | |
a246b010 CL |
703 | xprt_release_write(xprt, task); |
704 | else { | |
705 | if (task->tk_rqstp) | |
706 | task->tk_rqstp->rq_bytes_sent = 0; | |
1da177e4 | 707 | |
03bf4b70 | 708 | task->tk_timeout = xprt->connect_timeout; |
5d00837b | 709 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
262ca07d | 710 | xprt->stat.connect_start = jiffies; |
a246b010 | 711 | xprt->ops->connect(task); |
1da177e4 LT |
712 | } |
713 | return; | |
1da177e4 LT |
714 | } |
715 | ||
9903cd1c | 716 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 LT |
717 | { |
718 | struct rpc_xprt *xprt = task->tk_xprt; | |
719 | ||
cd983ef8 | 720 | if (task->tk_status == 0) { |
262ca07d CL |
721 | xprt->stat.connect_count++; |
722 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 723 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
724 | task->tk_pid); |
725 | return; | |
726 | } | |
727 | ||
1da177e4 | 728 | switch (task->tk_status) { |
2a491991 TM |
729 | case -EAGAIN: |
730 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 731 | break; |
1da177e4 | 732 | case -ETIMEDOUT: |
46121cf7 CL |
733 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
734 | "out\n", task->tk_pid); | |
1da177e4 LT |
735 | break; |
736 | default: | |
46121cf7 CL |
737 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
738 | "server %s\n", task->tk_pid, -task->tk_status, | |
739 | task->tk_client->cl_server); | |
23475d66 CL |
740 | xprt_release_write(xprt, task); |
741 | task->tk_status = -EIO; | |
1da177e4 | 742 | } |
1da177e4 LT |
743 | } |
744 | ||
9903cd1c CL |
745 | /** |
746 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
747 | * @xprt: transport on which the original request was transmitted | |
748 | * @xid: RPC XID of incoming reply | |
749 | * | |
1da177e4 | 750 | */ |
d8ed029d | 751 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 LT |
752 | { |
753 | struct list_head *pos; | |
1da177e4 LT |
754 | |
755 | list_for_each(pos, &xprt->recv) { | |
756 | struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); | |
262ca07d CL |
757 | if (entry->rq_xid == xid) |
758 | return entry; | |
1da177e4 | 759 | } |
46121cf7 CL |
760 | |
761 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
762 | ntohl(xid)); | |
262ca07d CL |
763 | xprt->stat.bad_xids++; |
764 | return NULL; | |
1da177e4 | 765 | } |
12444809 | 766 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 767 | |
1570c1e4 CL |
768 | /** |
769 | * xprt_update_rtt - update an RPC client's RTT state after receiving a reply | |
770 | * @task: RPC request that recently completed | |
771 | * | |
772 | */ | |
773 | void xprt_update_rtt(struct rpc_task *task) | |
774 | { | |
775 | struct rpc_rqst *req = task->tk_rqstp; | |
776 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
777 | unsigned timer = task->tk_msg.rpc_proc->p_timer; | |
778 | ||
779 | if (timer) { | |
780 | if (req->rq_ntrans == 1) | |
781 | rpc_update_rtt(rtt, timer, | |
782 | (long)jiffies - req->rq_xtime); | |
783 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); | |
784 | } | |
785 | } | |
12444809 | 786 | EXPORT_SYMBOL_GPL(xprt_update_rtt); |
1570c1e4 | 787 | |
9903cd1c CL |
788 | /** |
789 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 790 | * @task: RPC request that recently completed |
9903cd1c CL |
791 | * @copied: actual number of bytes received from the transport |
792 | * | |
1570c1e4 | 793 | * Caller holds transport lock. |
1da177e4 | 794 | */ |
1570c1e4 | 795 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 796 | { |
1570c1e4 | 797 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 798 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 799 | |
1570c1e4 CL |
800 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
801 | task->tk_pid, ntohl(req->rq_xid), copied); | |
1da177e4 | 802 | |
fda13939 | 803 | xprt->stat.recvs++; |
ef759a2e CL |
804 | task->tk_rtt = (long)jiffies - req->rq_xtime; |
805 | ||
1da177e4 | 806 | list_del_init(&req->rq_list); |
1e799b67 | 807 | req->rq_private_buf.len = copied; |
43ac3f29 TM |
808 | /* Ensure all writes are done before we update req->rq_received */ |
809 | smp_wmb(); | |
1e799b67 | 810 | req->rq_received = copied; |
fda13939 | 811 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 812 | } |
12444809 | 813 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 814 | |
46c0ee8b | 815 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 816 | { |
46c0ee8b | 817 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
818 | struct rpc_xprt *xprt = req->rq_xprt; |
819 | ||
5d00837b TM |
820 | if (task->tk_status != -ETIMEDOUT) |
821 | return; | |
46121cf7 | 822 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 823 | |
5d00837b | 824 | spin_lock_bh(&xprt->transport_lock); |
46c0ee8b CL |
825 | if (!req->rq_received) { |
826 | if (xprt->ops->timer) | |
827 | xprt->ops->timer(task); | |
5d00837b TM |
828 | } else |
829 | task->tk_status = 0; | |
830 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
831 | } |
832 | ||
9903cd1c CL |
833 | /** |
834 | * xprt_prepare_transmit - reserve the transport before sending a request | |
835 | * @task: RPC task about to send a request | |
836 | * | |
1da177e4 | 837 | */ |
9903cd1c | 838 | int xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
839 | { |
840 | struct rpc_rqst *req = task->tk_rqstp; | |
841 | struct rpc_xprt *xprt = req->rq_xprt; | |
842 | int err = 0; | |
843 | ||
46121cf7 | 844 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 845 | |
4a0f8c04 | 846 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
847 | if (req->rq_received && !req->rq_bytes_sent) { |
848 | err = req->rq_received; | |
849 | goto out_unlock; | |
850 | } | |
2a491991 | 851 | if (!xprt->ops->reserve_xprt(task)) |
1da177e4 | 852 | err = -EAGAIN; |
1da177e4 | 853 | out_unlock: |
4a0f8c04 | 854 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
855 | return err; |
856 | } | |
857 | ||
e0ab53de | 858 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 859 | { |
e0ab53de | 860 | xprt_release_write(task->tk_xprt, task); |
5e5ce5be TM |
861 | } |
862 | ||
9903cd1c CL |
863 | /** |
864 | * xprt_transmit - send an RPC request on a transport | |
865 | * @task: controlling RPC task | |
866 | * | |
867 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
868 | */ | |
869 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 870 | { |
1da177e4 LT |
871 | struct rpc_rqst *req = task->tk_rqstp; |
872 | struct rpc_xprt *xprt = req->rq_xprt; | |
a246b010 | 873 | int status; |
1da177e4 | 874 | |
46121cf7 | 875 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 876 | |
1da177e4 LT |
877 | if (!req->rq_received) { |
878 | if (list_empty(&req->rq_list)) { | |
4a0f8c04 | 879 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
880 | /* Update the softirq receive buffer */ |
881 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
882 | sizeof(req->rq_private_buf)); | |
883 | /* Add request to the receive list */ | |
884 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 885 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 886 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
887 | /* Turn off autodisconnect */ |
888 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
889 | } |
890 | } else if (!req->rq_bytes_sent) | |
891 | return; | |
892 | ||
7c1d71cf | 893 | req->rq_connect_cookie = xprt->connect_cookie; |
b22602a6 | 894 | req->rq_xtime = jiffies; |
a246b010 | 895 | status = xprt->ops->send_request(task); |
c8485e4d TM |
896 | if (status != 0) { |
897 | task->tk_status = status; | |
898 | return; | |
899 | } | |
262ca07d | 900 | |
c8485e4d TM |
901 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
902 | spin_lock_bh(&xprt->transport_lock); | |
262ca07d | 903 | |
c8485e4d | 904 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 905 | |
c8485e4d TM |
906 | xprt->stat.sends++; |
907 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
908 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
1da177e4 | 909 | |
c8485e4d TM |
910 | /* Don't race with disconnect */ |
911 | if (!xprt_connected(xprt)) | |
912 | task->tk_status = -ENOTCONN; | |
913 | else if (!req->rq_received) | |
914 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
915 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
916 | } |
917 | ||
9903cd1c | 918 | static inline void do_xprt_reserve(struct rpc_task *task) |
1da177e4 LT |
919 | { |
920 | struct rpc_xprt *xprt = task->tk_xprt; | |
921 | ||
922 | task->tk_status = 0; | |
923 | if (task->tk_rqstp) | |
924 | return; | |
925 | if (!list_empty(&xprt->free)) { | |
926 | struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); | |
927 | list_del_init(&req->rq_list); | |
928 | task->tk_rqstp = req; | |
929 | xprt_request_init(task, xprt); | |
930 | return; | |
931 | } | |
46121cf7 | 932 | dprintk("RPC: waiting for request slot\n"); |
1da177e4 LT |
933 | task->tk_status = -EAGAIN; |
934 | task->tk_timeout = 0; | |
5d00837b | 935 | rpc_sleep_on(&xprt->backlog, task, NULL); |
1da177e4 LT |
936 | } |
937 | ||
9903cd1c CL |
938 | /** |
939 | * xprt_reserve - allocate an RPC request slot | |
940 | * @task: RPC task requesting a slot allocation | |
941 | * | |
942 | * If no more slots are available, place the task on the transport's | |
943 | * backlog queue. | |
944 | */ | |
945 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 LT |
946 | { |
947 | struct rpc_xprt *xprt = task->tk_xprt; | |
948 | ||
949 | task->tk_status = -EIO; | |
0065db32 TM |
950 | spin_lock(&xprt->reserve_lock); |
951 | do_xprt_reserve(task); | |
952 | spin_unlock(&xprt->reserve_lock); | |
1da177e4 LT |
953 | } |
954 | ||
d8ed029d | 955 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 LT |
956 | { |
957 | return xprt->xid++; | |
958 | } | |
959 | ||
960 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
961 | { | |
bf3fcf89 | 962 | xprt->xid = net_random(); |
1da177e4 LT |
963 | } |
964 | ||
9903cd1c | 965 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
966 | { |
967 | struct rpc_rqst *req = task->tk_rqstp; | |
968 | ||
ba7392bb | 969 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
970 | req->rq_task = task; |
971 | req->rq_xprt = xprt; | |
02107148 | 972 | req->rq_buffer = NULL; |
1da177e4 | 973 | req->rq_xid = xprt_alloc_xid(xprt); |
ead5e1c2 | 974 | req->rq_release_snd_buf = NULL; |
da45828e | 975 | xprt_reset_majortimeo(req); |
46121cf7 | 976 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
977 | req, ntohl(req->rq_xid)); |
978 | } | |
979 | ||
9903cd1c CL |
980 | /** |
981 | * xprt_release - release an RPC request slot | |
982 | * @task: task which is finished with the slot | |
983 | * | |
1da177e4 | 984 | */ |
9903cd1c | 985 | void xprt_release(struct rpc_task *task) |
1da177e4 LT |
986 | { |
987 | struct rpc_xprt *xprt = task->tk_xprt; | |
988 | struct rpc_rqst *req; | |
989 | ||
990 | if (!(req = task->tk_rqstp)) | |
991 | return; | |
11c556b3 | 992 | rpc_count_iostats(task); |
4a0f8c04 | 993 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 994 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
995 | if (xprt->ops->release_request) |
996 | xprt->ops->release_request(task); | |
1da177e4 LT |
997 | if (!list_empty(&req->rq_list)) |
998 | list_del(&req->rq_list); | |
999 | xprt->last_used = jiffies; | |
0065db32 | 1000 | if (list_empty(&xprt->recv)) |
a246b010 | 1001 | mod_timer(&xprt->timer, |
03bf4b70 | 1002 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1003 | spin_unlock_bh(&xprt->transport_lock); |
c5a4dd8b | 1004 | xprt->ops->buf_free(req->rq_buffer); |
1da177e4 | 1005 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1006 | if (req->rq_release_snd_buf) |
1007 | req->rq_release_snd_buf(req); | |
1da177e4 LT |
1008 | memset(req, 0, sizeof(*req)); /* mark unused */ |
1009 | ||
46121cf7 | 1010 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
1da177e4 | 1011 | |
5dc07727 | 1012 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 1013 | list_add(&req->rq_list, &xprt->free); |
555ee3af | 1014 | rpc_wake_up_next(&xprt->backlog); |
5dc07727 | 1015 | spin_unlock(&xprt->reserve_lock); |
1da177e4 LT |
1016 | } |
1017 | ||
c2866763 CL |
1018 | /** |
1019 | * xprt_create_transport - create an RPC transport | |
96802a09 | 1020 | * @args: rpc transport creation arguments |
c2866763 CL |
1021 | * |
1022 | */ | |
3c341b0b | 1023 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) |
c2866763 | 1024 | { |
c2866763 CL |
1025 | struct rpc_xprt *xprt; |
1026 | struct rpc_rqst *req; | |
bc25571e | 1027 | struct xprt_class *t; |
c2866763 | 1028 | |
bc25571e TT |
1029 | spin_lock(&xprt_list_lock); |
1030 | list_for_each_entry(t, &xprt_list, list) { | |
4fa016eb | 1031 | if (t->ident == args->ident) { |
bc25571e TT |
1032 | spin_unlock(&xprt_list_lock); |
1033 | goto found; | |
1034 | } | |
c2866763 | 1035 | } |
bc25571e | 1036 | spin_unlock(&xprt_list_lock); |
4fa016eb | 1037 | printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); |
bc25571e TT |
1038 | return ERR_PTR(-EIO); |
1039 | ||
1040 | found: | |
1041 | xprt = t->setup(args); | |
c8541ecd | 1042 | if (IS_ERR(xprt)) { |
46121cf7 | 1043 | dprintk("RPC: xprt_create_transport: failed, %ld\n", |
c8541ecd CL |
1044 | -PTR_ERR(xprt)); |
1045 | return xprt; | |
c2866763 CL |
1046 | } |
1047 | ||
6b6ca86b | 1048 | kref_init(&xprt->kref); |
c2866763 CL |
1049 | spin_lock_init(&xprt->transport_lock); |
1050 | spin_lock_init(&xprt->reserve_lock); | |
1051 | ||
1052 | INIT_LIST_HEAD(&xprt->free); | |
1053 | INIT_LIST_HEAD(&xprt->recv); | |
65f27f38 | 1054 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
b24b8a24 PE |
1055 | setup_timer(&xprt->timer, xprt_init_autodisconnect, |
1056 | (unsigned long)xprt); | |
c2866763 CL |
1057 | xprt->last_used = jiffies; |
1058 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1059 | xprt->bind_index = 0; |
c2866763 CL |
1060 | |
1061 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1062 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
1063 | rpc_init_wait_queue(&xprt->sending, "xprt_sending"); | |
1064 | rpc_init_wait_queue(&xprt->resend, "xprt_resend"); | |
1065 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); | |
1066 | ||
1067 | /* initialize free list */ | |
1068 | for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) | |
1069 | list_add(&req->rq_list, &xprt->free); | |
1070 | ||
1071 | xprt_init_xid(xprt); | |
1072 | ||
46121cf7 | 1073 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 CL |
1074 | xprt->max_reqs); |
1075 | ||
1076 | return xprt; | |
1077 | } | |
1078 | ||
9903cd1c CL |
1079 | /** |
1080 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
6b6ca86b | 1081 | * @kref: kref for the transport to destroy |
9903cd1c | 1082 | * |
1da177e4 | 1083 | */ |
6b6ca86b | 1084 | static void xprt_destroy(struct kref *kref) |
1da177e4 | 1085 | { |
6b6ca86b TM |
1086 | struct rpc_xprt *xprt = container_of(kref, struct rpc_xprt, kref); |
1087 | ||
46121cf7 | 1088 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 TM |
1089 | xprt->shutdown = 1; |
1090 | del_timer_sync(&xprt->timer); | |
c8541ecd | 1091 | |
f6a1cc89 TM |
1092 | rpc_destroy_wait_queue(&xprt->binding); |
1093 | rpc_destroy_wait_queue(&xprt->pending); | |
1094 | rpc_destroy_wait_queue(&xprt->sending); | |
1095 | rpc_destroy_wait_queue(&xprt->resend); | |
1096 | rpc_destroy_wait_queue(&xprt->backlog); | |
c8541ecd CL |
1097 | /* |
1098 | * Tear down transport state and free the rpc_xprt | |
1099 | */ | |
a246b010 | 1100 | xprt->ops->destroy(xprt); |
6b6ca86b | 1101 | } |
1da177e4 | 1102 | |
6b6ca86b TM |
1103 | /** |
1104 | * xprt_put - release a reference to an RPC transport. | |
1105 | * @xprt: pointer to the transport | |
1106 | * | |
1107 | */ | |
1108 | void xprt_put(struct rpc_xprt *xprt) | |
1109 | { | |
1110 | kref_put(&xprt->kref, xprt_destroy); | |
1111 | } | |
1112 | ||
1113 | /** | |
1114 | * xprt_get - return a reference to an RPC transport. | |
1115 | * @xprt: pointer to the transport | |
1116 | * | |
1117 | */ | |
1118 | struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) | |
1119 | { | |
1120 | kref_get(&xprt->kref); | |
1121 | return xprt; | |
1da177e4 | 1122 | } |