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Commit | Line | Data |
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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 | ||
555ee3af CL |
65 | /* |
66 | * The transport code maintains an estimate on the maximum number of out- | |
67 | * standing RPC requests, using a smoothed version of the congestion | |
68 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
69 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
70 | * halved; otherwise, it is incremented by 1/cwnd when | |
71 | * | |
72 | * - a reply is received and | |
73 | * - a full number of requests are outstanding and | |
74 | * - the congestion window hasn't been updated recently. | |
75 | */ | |
76 | #define RPC_CWNDSHIFT (8U) | |
77 | #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) | |
78 | #define RPC_INITCWND RPC_CWNDSCALE | |
79 | #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) | |
80 | ||
81 | #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) | |
1da177e4 | 82 | |
12a80469 CL |
83 | /** |
84 | * xprt_reserve_xprt - serialize write access to transports | |
85 | * @task: task that is requesting access to the transport | |
86 | * | |
87 | * This prevents mixing the payload of separate requests, and prevents | |
88 | * transport connects from colliding with writes. No congestion control | |
89 | * is provided. | |
90 | */ | |
91 | int xprt_reserve_xprt(struct rpc_task *task) | |
92 | { | |
93 | struct rpc_xprt *xprt = task->tk_xprt; | |
94 | struct rpc_rqst *req = task->tk_rqstp; | |
95 | ||
96 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
97 | if (task == xprt->snd_task) | |
98 | return 1; | |
99 | if (task == NULL) | |
100 | return 0; | |
101 | goto out_sleep; | |
102 | } | |
103 | xprt->snd_task = task; | |
104 | if (req) { | |
105 | req->rq_bytes_sent = 0; | |
106 | req->rq_ntrans++; | |
107 | } | |
108 | return 1; | |
109 | ||
110 | out_sleep: | |
46121cf7 | 111 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
112 | task->tk_pid, xprt); |
113 | task->tk_timeout = 0; | |
114 | task->tk_status = -EAGAIN; | |
115 | if (req && req->rq_ntrans) | |
116 | rpc_sleep_on(&xprt->resend, task, NULL, NULL); | |
117 | else | |
118 | rpc_sleep_on(&xprt->sending, task, NULL, NULL); | |
119 | return 0; | |
120 | } | |
12444809 | 121 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 122 | |
632e3bdc TM |
123 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
124 | { | |
125 | xprt->snd_task = NULL; | |
126 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { | |
127 | smp_mb__before_clear_bit(); | |
128 | clear_bit(XPRT_LOCKED, &xprt->state); | |
129 | smp_mb__after_clear_bit(); | |
130 | } else | |
c1384c9c | 131 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
132 | } |
133 | ||
1da177e4 | 134 | /* |
12a80469 CL |
135 | * xprt_reserve_xprt_cong - serialize write access to transports |
136 | * @task: task that is requesting access to the transport | |
137 | * | |
138 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
139 | * integrated into the decision of whether a request is allowed to be | |
140 | * woken up and given access to the transport. | |
1da177e4 | 141 | */ |
12a80469 | 142 | int xprt_reserve_xprt_cong(struct rpc_task *task) |
1da177e4 | 143 | { |
12a80469 | 144 | struct rpc_xprt *xprt = task->tk_xprt; |
1da177e4 LT |
145 | struct rpc_rqst *req = task->tk_rqstp; |
146 | ||
2226feb6 | 147 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
148 | if (task == xprt->snd_task) |
149 | return 1; | |
1da177e4 LT |
150 | goto out_sleep; |
151 | } | |
12a80469 | 152 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
153 | xprt->snd_task = task; |
154 | if (req) { | |
155 | req->rq_bytes_sent = 0; | |
156 | req->rq_ntrans++; | |
157 | } | |
158 | return 1; | |
159 | } | |
632e3bdc | 160 | xprt_clear_locked(xprt); |
1da177e4 | 161 | out_sleep: |
46121cf7 | 162 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
163 | task->tk_timeout = 0; |
164 | task->tk_status = -EAGAIN; | |
165 | if (req && req->rq_ntrans) | |
166 | rpc_sleep_on(&xprt->resend, task, NULL, NULL); | |
167 | else | |
168 | rpc_sleep_on(&xprt->sending, task, NULL, NULL); | |
169 | return 0; | |
170 | } | |
12444809 | 171 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 172 | |
12a80469 | 173 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
174 | { |
175 | int retval; | |
176 | ||
4a0f8c04 | 177 | spin_lock_bh(&xprt->transport_lock); |
12a80469 | 178 | retval = xprt->ops->reserve_xprt(task); |
4a0f8c04 | 179 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
180 | return retval; |
181 | } | |
182 | ||
12a80469 | 183 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
49e9a890 CL |
184 | { |
185 | struct rpc_task *task; | |
186 | struct rpc_rqst *req; | |
187 | ||
188 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
189 | return; | |
190 | ||
191 | task = rpc_wake_up_next(&xprt->resend); | |
192 | if (!task) { | |
193 | task = rpc_wake_up_next(&xprt->sending); | |
194 | if (!task) | |
195 | goto out_unlock; | |
196 | } | |
197 | ||
198 | req = task->tk_rqstp; | |
199 | xprt->snd_task = task; | |
200 | if (req) { | |
201 | req->rq_bytes_sent = 0; | |
202 | req->rq_ntrans++; | |
203 | } | |
204 | return; | |
205 | ||
206 | out_unlock: | |
632e3bdc | 207 | xprt_clear_locked(xprt); |
49e9a890 CL |
208 | } |
209 | ||
210 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
1da177e4 LT |
211 | { |
212 | struct rpc_task *task; | |
213 | ||
2226feb6 | 214 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 215 | return; |
49e9a890 | 216 | if (RPCXPRT_CONGESTED(xprt)) |
1da177e4 LT |
217 | goto out_unlock; |
218 | task = rpc_wake_up_next(&xprt->resend); | |
219 | if (!task) { | |
220 | task = rpc_wake_up_next(&xprt->sending); | |
221 | if (!task) | |
222 | goto out_unlock; | |
223 | } | |
49e9a890 | 224 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
225 | struct rpc_rqst *req = task->tk_rqstp; |
226 | xprt->snd_task = task; | |
227 | if (req) { | |
228 | req->rq_bytes_sent = 0; | |
229 | req->rq_ntrans++; | |
230 | } | |
231 | return; | |
232 | } | |
233 | out_unlock: | |
632e3bdc | 234 | xprt_clear_locked(xprt); |
1da177e4 LT |
235 | } |
236 | ||
49e9a890 CL |
237 | /** |
238 | * xprt_release_xprt - allow other requests to use a transport | |
239 | * @xprt: transport with other tasks potentially waiting | |
240 | * @task: task that is releasing access to the transport | |
241 | * | |
242 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 243 | */ |
49e9a890 | 244 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
245 | { |
246 | if (xprt->snd_task == task) { | |
632e3bdc | 247 | xprt_clear_locked(xprt); |
1da177e4 LT |
248 | __xprt_lock_write_next(xprt); |
249 | } | |
250 | } | |
12444809 | 251 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 252 | |
49e9a890 CL |
253 | /** |
254 | * xprt_release_xprt_cong - allow other requests to use a transport | |
255 | * @xprt: transport with other tasks potentially waiting | |
256 | * @task: task that is releasing access to the transport | |
257 | * | |
258 | * Note that "task" can be NULL. Another task is awoken to use the | |
259 | * transport if the transport's congestion window allows it. | |
260 | */ | |
261 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
262 | { | |
263 | if (xprt->snd_task == task) { | |
632e3bdc | 264 | xprt_clear_locked(xprt); |
49e9a890 CL |
265 | __xprt_lock_write_next_cong(xprt); |
266 | } | |
267 | } | |
12444809 | 268 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
269 | |
270 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 271 | { |
4a0f8c04 | 272 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 273 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 274 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
275 | } |
276 | ||
1da177e4 LT |
277 | /* |
278 | * Van Jacobson congestion avoidance. Check if the congestion window | |
279 | * overflowed. Put the task to sleep if this is the case. | |
280 | */ | |
281 | static int | |
282 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
283 | { | |
284 | struct rpc_rqst *req = task->tk_rqstp; | |
285 | ||
286 | if (req->rq_cong) | |
287 | return 1; | |
46121cf7 | 288 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
289 | task->tk_pid, xprt->cong, xprt->cwnd); |
290 | if (RPCXPRT_CONGESTED(xprt)) | |
291 | return 0; | |
292 | req->rq_cong = 1; | |
293 | xprt->cong += RPC_CWNDSCALE; | |
294 | return 1; | |
295 | } | |
296 | ||
297 | /* | |
298 | * Adjust the congestion window, and wake up the next task | |
299 | * that has been sleeping due to congestion | |
300 | */ | |
301 | static void | |
302 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
303 | { | |
304 | if (!req->rq_cong) | |
305 | return; | |
306 | req->rq_cong = 0; | |
307 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 308 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
309 | } |
310 | ||
a58dd398 CL |
311 | /** |
312 | * xprt_release_rqst_cong - housekeeping when request is complete | |
313 | * @task: RPC request that recently completed | |
314 | * | |
315 | * Useful for transports that require congestion control. | |
316 | */ | |
317 | void xprt_release_rqst_cong(struct rpc_task *task) | |
318 | { | |
319 | __xprt_put_cong(task->tk_xprt, task->tk_rqstp); | |
320 | } | |
12444809 | 321 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 322 | |
46c0ee8b CL |
323 | /** |
324 | * xprt_adjust_cwnd - adjust transport congestion window | |
325 | * @task: recently completed RPC request used to adjust window | |
326 | * @result: result code of completed RPC request | |
327 | * | |
1da177e4 LT |
328 | * We use a time-smoothed congestion estimator to avoid heavy oscillation. |
329 | */ | |
46c0ee8b | 330 | void xprt_adjust_cwnd(struct rpc_task *task, int result) |
1da177e4 | 331 | { |
46c0ee8b CL |
332 | struct rpc_rqst *req = task->tk_rqstp; |
333 | struct rpc_xprt *xprt = task->tk_xprt; | |
334 | unsigned long cwnd = xprt->cwnd; | |
1da177e4 | 335 | |
1da177e4 LT |
336 | if (result >= 0 && cwnd <= xprt->cong) { |
337 | /* The (cwnd >> 1) term makes sure | |
338 | * the result gets rounded properly. */ | |
339 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
340 | if (cwnd > RPC_MAXCWND(xprt)) | |
341 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 342 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
343 | } else if (result == -ETIMEDOUT) { |
344 | cwnd >>= 1; | |
345 | if (cwnd < RPC_CWNDSCALE) | |
346 | cwnd = RPC_CWNDSCALE; | |
347 | } | |
46121cf7 | 348 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
349 | xprt->cong, xprt->cwnd, cwnd); |
350 | xprt->cwnd = cwnd; | |
46c0ee8b | 351 | __xprt_put_cong(xprt, req); |
1da177e4 | 352 | } |
12444809 | 353 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 354 | |
44fbac22 CL |
355 | /** |
356 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
357 | * @xprt: transport with waiting tasks | |
358 | * @status: result code to plant in each task before waking it | |
359 | * | |
360 | */ | |
361 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
362 | { | |
363 | if (status < 0) | |
364 | rpc_wake_up_status(&xprt->pending, status); | |
365 | else | |
366 | rpc_wake_up(&xprt->pending); | |
367 | } | |
12444809 | 368 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 369 | |
c7b2cae8 CL |
370 | /** |
371 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
372 | * @task: task to be put to sleep | |
373 | * | |
374 | */ | |
375 | void xprt_wait_for_buffer_space(struct rpc_task *task) | |
376 | { | |
377 | struct rpc_rqst *req = task->tk_rqstp; | |
378 | struct rpc_xprt *xprt = req->rq_xprt; | |
379 | ||
380 | task->tk_timeout = req->rq_timeout; | |
381 | rpc_sleep_on(&xprt->pending, task, NULL, NULL); | |
382 | } | |
12444809 | 383 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
384 | |
385 | /** | |
386 | * xprt_write_space - wake the task waiting for transport output buffer space | |
387 | * @xprt: transport with waiting tasks | |
388 | * | |
389 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
390 | */ | |
391 | void xprt_write_space(struct rpc_xprt *xprt) | |
392 | { | |
393 | if (unlikely(xprt->shutdown)) | |
394 | return; | |
395 | ||
396 | spin_lock_bh(&xprt->transport_lock); | |
397 | if (xprt->snd_task) { | |
46121cf7 CL |
398 | dprintk("RPC: write space: waking waiting task on " |
399 | "xprt %p\n", xprt); | |
c7b2cae8 CL |
400 | rpc_wake_up_task(xprt->snd_task); |
401 | } | |
402 | spin_unlock_bh(&xprt->transport_lock); | |
403 | } | |
12444809 | 404 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 405 | |
fe3aca29 CL |
406 | /** |
407 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
408 | * @task: task whose timeout is to be set | |
409 | * | |
410 | * Set a request's retransmit timeout based on the transport's | |
411 | * default timeout parameters. Used by transports that don't adjust | |
412 | * the retransmit timeout based on round-trip time estimation. | |
413 | */ | |
414 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
415 | { | |
416 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
417 | } | |
12444809 | 418 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 CL |
419 | |
420 | /* | |
421 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout | |
422 | * @task: task whose timeout is to be set | |
cca5172a | 423 | * |
fe3aca29 CL |
424 | * Set a request's retransmit timeout using the RTT estimator. |
425 | */ | |
426 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
427 | { | |
428 | int timer = task->tk_msg.rpc_proc->p_timer; | |
429 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
430 | struct rpc_rqst *req = task->tk_rqstp; | |
431 | unsigned long max_timeout = req->rq_xprt->timeout.to_maxval; | |
432 | ||
433 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
434 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
435 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
436 | task->tk_timeout = max_timeout; | |
437 | } | |
12444809 | 438 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 439 | |
1da177e4 LT |
440 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
441 | { | |
442 | struct rpc_timeout *to = &req->rq_xprt->timeout; | |
443 | ||
444 | req->rq_majortimeo = req->rq_timeout; | |
445 | if (to->to_exponential) | |
446 | req->rq_majortimeo <<= to->to_retries; | |
447 | else | |
448 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
449 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
450 | req->rq_majortimeo = to->to_maxval; | |
451 | req->rq_majortimeo += jiffies; | |
452 | } | |
453 | ||
9903cd1c CL |
454 | /** |
455 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
456 | * @req: RPC request containing parameters to use for the adjustment | |
457 | * | |
1da177e4 LT |
458 | */ |
459 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
460 | { | |
461 | struct rpc_xprt *xprt = req->rq_xprt; | |
462 | struct rpc_timeout *to = &xprt->timeout; | |
463 | int status = 0; | |
464 | ||
465 | if (time_before(jiffies, req->rq_majortimeo)) { | |
466 | if (to->to_exponential) | |
467 | req->rq_timeout <<= 1; | |
468 | else | |
469 | req->rq_timeout += to->to_increment; | |
470 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
471 | req->rq_timeout = to->to_maxval; | |
472 | req->rq_retries++; | |
1da177e4 LT |
473 | } else { |
474 | req->rq_timeout = to->to_initval; | |
475 | req->rq_retries = 0; | |
476 | xprt_reset_majortimeo(req); | |
477 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 478 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 479 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 480 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
481 | status = -ETIMEDOUT; |
482 | } | |
483 | ||
484 | if (req->rq_timeout == 0) { | |
485 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
486 | req->rq_timeout = 5 * HZ; | |
487 | } | |
488 | return status; | |
489 | } | |
490 | ||
65f27f38 | 491 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 492 | { |
65f27f38 DH |
493 | struct rpc_xprt *xprt = |
494 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 LT |
495 | |
496 | xprt_disconnect(xprt); | |
a246b010 | 497 | xprt->ops->close(xprt); |
1da177e4 LT |
498 | xprt_release_write(xprt, NULL); |
499 | } | |
500 | ||
9903cd1c CL |
501 | /** |
502 | * xprt_disconnect - mark a transport as disconnected | |
503 | * @xprt: transport to flag for disconnect | |
504 | * | |
1da177e4 | 505 | */ |
a246b010 | 506 | void xprt_disconnect(struct rpc_xprt *xprt) |
1da177e4 | 507 | { |
46121cf7 | 508 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 509 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 510 | xprt_clear_connected(xprt); |
44fbac22 | 511 | xprt_wake_pending_tasks(xprt, -ENOTCONN); |
4a0f8c04 | 512 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 513 | } |
12444809 | 514 | EXPORT_SYMBOL_GPL(xprt_disconnect); |
1da177e4 | 515 | |
1da177e4 LT |
516 | static void |
517 | xprt_init_autodisconnect(unsigned long data) | |
518 | { | |
519 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
520 | ||
4a0f8c04 | 521 | spin_lock(&xprt->transport_lock); |
1da177e4 LT |
522 | if (!list_empty(&xprt->recv) || xprt->shutdown) |
523 | goto out_abort; | |
2226feb6 | 524 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 525 | goto out_abort; |
4a0f8c04 | 526 | spin_unlock(&xprt->transport_lock); |
2226feb6 | 527 | if (xprt_connecting(xprt)) |
1da177e4 LT |
528 | xprt_release_write(xprt, NULL); |
529 | else | |
c1384c9c | 530 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
1da177e4 LT |
531 | return; |
532 | out_abort: | |
4a0f8c04 | 533 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
534 | } |
535 | ||
9903cd1c CL |
536 | /** |
537 | * xprt_connect - schedule a transport connect operation | |
538 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
539 | * |
540 | */ | |
541 | void xprt_connect(struct rpc_task *task) | |
542 | { | |
543 | struct rpc_xprt *xprt = task->tk_xprt; | |
544 | ||
46121cf7 | 545 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
546 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
547 | ||
ec739ef0 | 548 | if (!xprt_bound(xprt)) { |
1da177e4 LT |
549 | task->tk_status = -EIO; |
550 | return; | |
551 | } | |
552 | if (!xprt_lock_write(xprt, task)) | |
553 | return; | |
554 | if (xprt_connected(xprt)) | |
a246b010 CL |
555 | xprt_release_write(xprt, task); |
556 | else { | |
557 | if (task->tk_rqstp) | |
558 | task->tk_rqstp->rq_bytes_sent = 0; | |
1da177e4 | 559 | |
03bf4b70 | 560 | task->tk_timeout = xprt->connect_timeout; |
a246b010 | 561 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status, NULL); |
262ca07d | 562 | xprt->stat.connect_start = jiffies; |
a246b010 | 563 | xprt->ops->connect(task); |
1da177e4 LT |
564 | } |
565 | return; | |
1da177e4 LT |
566 | } |
567 | ||
9903cd1c | 568 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 LT |
569 | { |
570 | struct rpc_xprt *xprt = task->tk_xprt; | |
571 | ||
572 | if (task->tk_status >= 0) { | |
262ca07d CL |
573 | xprt->stat.connect_count++; |
574 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 575 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
576 | task->tk_pid); |
577 | return; | |
578 | } | |
579 | ||
1da177e4 LT |
580 | switch (task->tk_status) { |
581 | case -ECONNREFUSED: | |
582 | case -ECONNRESET: | |
46121cf7 CL |
583 | dprintk("RPC: %5u xprt_connect_status: server %s refused " |
584 | "connection\n", task->tk_pid, | |
585 | task->tk_client->cl_server); | |
23475d66 | 586 | break; |
1da177e4 | 587 | case -ENOTCONN: |
46121cf7 | 588 | dprintk("RPC: %5u xprt_connect_status: connection broken\n", |
23475d66 CL |
589 | task->tk_pid); |
590 | break; | |
1da177e4 | 591 | case -ETIMEDOUT: |
46121cf7 CL |
592 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
593 | "out\n", task->tk_pid); | |
1da177e4 LT |
594 | break; |
595 | default: | |
46121cf7 CL |
596 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
597 | "server %s\n", task->tk_pid, -task->tk_status, | |
598 | task->tk_client->cl_server); | |
23475d66 CL |
599 | xprt_release_write(xprt, task); |
600 | task->tk_status = -EIO; | |
1da177e4 | 601 | } |
1da177e4 LT |
602 | } |
603 | ||
9903cd1c CL |
604 | /** |
605 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
606 | * @xprt: transport on which the original request was transmitted | |
607 | * @xid: RPC XID of incoming reply | |
608 | * | |
1da177e4 | 609 | */ |
d8ed029d | 610 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 LT |
611 | { |
612 | struct list_head *pos; | |
1da177e4 LT |
613 | |
614 | list_for_each(pos, &xprt->recv) { | |
615 | struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); | |
262ca07d CL |
616 | if (entry->rq_xid == xid) |
617 | return entry; | |
1da177e4 | 618 | } |
46121cf7 CL |
619 | |
620 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
621 | ntohl(xid)); | |
262ca07d CL |
622 | xprt->stat.bad_xids++; |
623 | return NULL; | |
1da177e4 | 624 | } |
12444809 | 625 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 626 | |
1570c1e4 CL |
627 | /** |
628 | * xprt_update_rtt - update an RPC client's RTT state after receiving a reply | |
629 | * @task: RPC request that recently completed | |
630 | * | |
631 | */ | |
632 | void xprt_update_rtt(struct rpc_task *task) | |
633 | { | |
634 | struct rpc_rqst *req = task->tk_rqstp; | |
635 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
636 | unsigned timer = task->tk_msg.rpc_proc->p_timer; | |
637 | ||
638 | if (timer) { | |
639 | if (req->rq_ntrans == 1) | |
640 | rpc_update_rtt(rtt, timer, | |
641 | (long)jiffies - req->rq_xtime); | |
642 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); | |
643 | } | |
644 | } | |
12444809 | 645 | EXPORT_SYMBOL_GPL(xprt_update_rtt); |
1570c1e4 | 646 | |
9903cd1c CL |
647 | /** |
648 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 649 | * @task: RPC request that recently completed |
9903cd1c CL |
650 | * @copied: actual number of bytes received from the transport |
651 | * | |
1570c1e4 | 652 | * Caller holds transport lock. |
1da177e4 | 653 | */ |
1570c1e4 | 654 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 655 | { |
1570c1e4 | 656 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 | 657 | |
1570c1e4 CL |
658 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
659 | task->tk_pid, ntohl(req->rq_xid), copied); | |
1da177e4 | 660 | |
262ca07d | 661 | task->tk_xprt->stat.recvs++; |
ef759a2e CL |
662 | task->tk_rtt = (long)jiffies - req->rq_xtime; |
663 | ||
1da177e4 | 664 | list_del_init(&req->rq_list); |
43ac3f29 TM |
665 | /* Ensure all writes are done before we update req->rq_received */ |
666 | smp_wmb(); | |
1da177e4 | 667 | req->rq_received = req->rq_private_buf.len = copied; |
1da177e4 | 668 | rpc_wake_up_task(task); |
1da177e4 | 669 | } |
12444809 | 670 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 671 | |
46c0ee8b | 672 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 673 | { |
46c0ee8b | 674 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
675 | struct rpc_xprt *xprt = req->rq_xprt; |
676 | ||
46121cf7 | 677 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 678 | |
46c0ee8b CL |
679 | spin_lock(&xprt->transport_lock); |
680 | if (!req->rq_received) { | |
681 | if (xprt->ops->timer) | |
682 | xprt->ops->timer(task); | |
683 | task->tk_status = -ETIMEDOUT; | |
684 | } | |
1da177e4 LT |
685 | task->tk_timeout = 0; |
686 | rpc_wake_up_task(task); | |
4a0f8c04 | 687 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
688 | } |
689 | ||
9903cd1c CL |
690 | /** |
691 | * xprt_prepare_transmit - reserve the transport before sending a request | |
692 | * @task: RPC task about to send a request | |
693 | * | |
1da177e4 | 694 | */ |
9903cd1c | 695 | int xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
696 | { |
697 | struct rpc_rqst *req = task->tk_rqstp; | |
698 | struct rpc_xprt *xprt = req->rq_xprt; | |
699 | int err = 0; | |
700 | ||
46121cf7 | 701 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 702 | |
4a0f8c04 | 703 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
704 | if (req->rq_received && !req->rq_bytes_sent) { |
705 | err = req->rq_received; | |
706 | goto out_unlock; | |
707 | } | |
12a80469 | 708 | if (!xprt->ops->reserve_xprt(task)) { |
1da177e4 LT |
709 | err = -EAGAIN; |
710 | goto out_unlock; | |
711 | } | |
712 | ||
713 | if (!xprt_connected(xprt)) { | |
714 | err = -ENOTCONN; | |
715 | goto out_unlock; | |
716 | } | |
717 | out_unlock: | |
4a0f8c04 | 718 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
719 | return err; |
720 | } | |
721 | ||
e0ab53de | 722 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 723 | { |
e0ab53de | 724 | xprt_release_write(task->tk_xprt, task); |
5e5ce5be TM |
725 | } |
726 | ||
9903cd1c CL |
727 | /** |
728 | * xprt_transmit - send an RPC request on a transport | |
729 | * @task: controlling RPC task | |
730 | * | |
731 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
732 | */ | |
733 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 734 | { |
1da177e4 LT |
735 | struct rpc_rqst *req = task->tk_rqstp; |
736 | struct rpc_xprt *xprt = req->rq_xprt; | |
a246b010 | 737 | int status; |
1da177e4 | 738 | |
46121cf7 | 739 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 740 | |
1da177e4 LT |
741 | if (!req->rq_received) { |
742 | if (list_empty(&req->rq_list)) { | |
4a0f8c04 | 743 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
744 | /* Update the softirq receive buffer */ |
745 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
746 | sizeof(req->rq_private_buf)); | |
747 | /* Add request to the receive list */ | |
748 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 749 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 750 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
751 | /* Turn off autodisconnect */ |
752 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
753 | } |
754 | } else if (!req->rq_bytes_sent) | |
755 | return; | |
756 | ||
a246b010 | 757 | status = xprt->ops->send_request(task); |
fe3aca29 | 758 | if (status == 0) { |
46121cf7 | 759 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
fe3aca29 | 760 | spin_lock_bh(&xprt->transport_lock); |
262ca07d | 761 | |
fe3aca29 | 762 | xprt->ops->set_retrans_timeout(task); |
262ca07d CL |
763 | |
764 | xprt->stat.sends++; | |
765 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
766 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
767 | ||
fe3aca29 CL |
768 | /* Don't race with disconnect */ |
769 | if (!xprt_connected(xprt)) | |
770 | task->tk_status = -ENOTCONN; | |
771 | else if (!req->rq_received) | |
772 | rpc_sleep_on(&xprt->pending, task, NULL, xprt_timer); | |
fe3aca29 CL |
773 | spin_unlock_bh(&xprt->transport_lock); |
774 | return; | |
775 | } | |
1da177e4 LT |
776 | |
777 | /* Note: at this point, task->tk_sleeping has not yet been set, | |
778 | * hence there is no danger of the waking up task being put on | |
779 | * schedq, and being picked up by a parallel run of rpciod(). | |
780 | */ | |
781 | task->tk_status = status; | |
e0ab53de | 782 | if (status == -ECONNREFUSED) |
1da177e4 | 783 | rpc_sleep_on(&xprt->sending, task, NULL, NULL); |
1da177e4 LT |
784 | } |
785 | ||
9903cd1c | 786 | static inline void do_xprt_reserve(struct rpc_task *task) |
1da177e4 LT |
787 | { |
788 | struct rpc_xprt *xprt = task->tk_xprt; | |
789 | ||
790 | task->tk_status = 0; | |
791 | if (task->tk_rqstp) | |
792 | return; | |
793 | if (!list_empty(&xprt->free)) { | |
794 | struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); | |
795 | list_del_init(&req->rq_list); | |
796 | task->tk_rqstp = req; | |
797 | xprt_request_init(task, xprt); | |
798 | return; | |
799 | } | |
46121cf7 | 800 | dprintk("RPC: waiting for request slot\n"); |
1da177e4 LT |
801 | task->tk_status = -EAGAIN; |
802 | task->tk_timeout = 0; | |
803 | rpc_sleep_on(&xprt->backlog, task, NULL, NULL); | |
804 | } | |
805 | ||
9903cd1c CL |
806 | /** |
807 | * xprt_reserve - allocate an RPC request slot | |
808 | * @task: RPC task requesting a slot allocation | |
809 | * | |
810 | * If no more slots are available, place the task on the transport's | |
811 | * backlog queue. | |
812 | */ | |
813 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 LT |
814 | { |
815 | struct rpc_xprt *xprt = task->tk_xprt; | |
816 | ||
817 | task->tk_status = -EIO; | |
0065db32 TM |
818 | spin_lock(&xprt->reserve_lock); |
819 | do_xprt_reserve(task); | |
820 | spin_unlock(&xprt->reserve_lock); | |
1da177e4 LT |
821 | } |
822 | ||
d8ed029d | 823 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 LT |
824 | { |
825 | return xprt->xid++; | |
826 | } | |
827 | ||
828 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
829 | { | |
bf3fcf89 | 830 | xprt->xid = net_random(); |
1da177e4 LT |
831 | } |
832 | ||
9903cd1c | 833 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
834 | { |
835 | struct rpc_rqst *req = task->tk_rqstp; | |
836 | ||
837 | req->rq_timeout = xprt->timeout.to_initval; | |
838 | req->rq_task = task; | |
839 | req->rq_xprt = xprt; | |
02107148 | 840 | req->rq_buffer = NULL; |
1da177e4 | 841 | req->rq_xid = xprt_alloc_xid(xprt); |
ead5e1c2 | 842 | req->rq_release_snd_buf = NULL; |
da45828e | 843 | xprt_reset_majortimeo(req); |
46121cf7 | 844 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
845 | req, ntohl(req->rq_xid)); |
846 | } | |
847 | ||
9903cd1c CL |
848 | /** |
849 | * xprt_release - release an RPC request slot | |
850 | * @task: task which is finished with the slot | |
851 | * | |
1da177e4 | 852 | */ |
9903cd1c | 853 | void xprt_release(struct rpc_task *task) |
1da177e4 LT |
854 | { |
855 | struct rpc_xprt *xprt = task->tk_xprt; | |
856 | struct rpc_rqst *req; | |
857 | ||
858 | if (!(req = task->tk_rqstp)) | |
859 | return; | |
11c556b3 | 860 | rpc_count_iostats(task); |
4a0f8c04 | 861 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 862 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
863 | if (xprt->ops->release_request) |
864 | xprt->ops->release_request(task); | |
1da177e4 LT |
865 | if (!list_empty(&req->rq_list)) |
866 | list_del(&req->rq_list); | |
867 | xprt->last_used = jiffies; | |
0065db32 | 868 | if (list_empty(&xprt->recv)) |
a246b010 | 869 | mod_timer(&xprt->timer, |
03bf4b70 | 870 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 871 | spin_unlock_bh(&xprt->transport_lock); |
c5a4dd8b | 872 | xprt->ops->buf_free(req->rq_buffer); |
1da177e4 | 873 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
874 | if (req->rq_release_snd_buf) |
875 | req->rq_release_snd_buf(req); | |
1da177e4 LT |
876 | memset(req, 0, sizeof(*req)); /* mark unused */ |
877 | ||
46121cf7 | 878 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
1da177e4 | 879 | |
5dc07727 | 880 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 881 | list_add(&req->rq_list, &xprt->free); |
555ee3af | 882 | rpc_wake_up_next(&xprt->backlog); |
5dc07727 | 883 | spin_unlock(&xprt->reserve_lock); |
1da177e4 LT |
884 | } |
885 | ||
9903cd1c CL |
886 | /** |
887 | * xprt_set_timeout - set constant RPC timeout | |
888 | * @to: RPC timeout parameters to set up | |
889 | * @retr: number of retries | |
890 | * @incr: amount of increase after each retry | |
891 | * | |
1da177e4 | 892 | */ |
9903cd1c | 893 | void xprt_set_timeout(struct rpc_timeout *to, unsigned int retr, unsigned long incr) |
1da177e4 | 894 | { |
cca5172a | 895 | to->to_initval = |
1da177e4 | 896 | to->to_increment = incr; |
eab5c084 | 897 | to->to_maxval = to->to_initval + (incr * retr); |
1da177e4 LT |
898 | to->to_retries = retr; |
899 | to->to_exponential = 0; | |
900 | } | |
901 | ||
c2866763 CL |
902 | /** |
903 | * xprt_create_transport - create an RPC transport | |
96802a09 | 904 | * @args: rpc transport creation arguments |
c2866763 CL |
905 | * |
906 | */ | |
96802a09 | 907 | struct rpc_xprt *xprt_create_transport(struct rpc_xprtsock_create *args) |
c2866763 | 908 | { |
c2866763 CL |
909 | struct rpc_xprt *xprt; |
910 | struct rpc_rqst *req; | |
911 | ||
96802a09 | 912 | switch (args->proto) { |
c2866763 | 913 | case IPPROTO_UDP: |
96802a09 | 914 | xprt = xs_setup_udp(args); |
c2866763 CL |
915 | break; |
916 | case IPPROTO_TCP: | |
96802a09 | 917 | xprt = xs_setup_tcp(args); |
c2866763 CL |
918 | break; |
919 | default: | |
920 | printk(KERN_ERR "RPC: unrecognized transport protocol: %d\n", | |
96802a09 | 921 | args->proto); |
c2866763 CL |
922 | return ERR_PTR(-EIO); |
923 | } | |
c8541ecd | 924 | if (IS_ERR(xprt)) { |
46121cf7 | 925 | dprintk("RPC: xprt_create_transport: failed, %ld\n", |
c8541ecd CL |
926 | -PTR_ERR(xprt)); |
927 | return xprt; | |
c2866763 CL |
928 | } |
929 | ||
6b6ca86b | 930 | kref_init(&xprt->kref); |
c2866763 CL |
931 | spin_lock_init(&xprt->transport_lock); |
932 | spin_lock_init(&xprt->reserve_lock); | |
933 | ||
934 | INIT_LIST_HEAD(&xprt->free); | |
935 | INIT_LIST_HEAD(&xprt->recv); | |
65f27f38 | 936 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
c2866763 CL |
937 | init_timer(&xprt->timer); |
938 | xprt->timer.function = xprt_init_autodisconnect; | |
939 | xprt->timer.data = (unsigned long) xprt; | |
940 | xprt->last_used = jiffies; | |
941 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 942 | xprt->bind_index = 0; |
c2866763 CL |
943 | |
944 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
945 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
946 | rpc_init_wait_queue(&xprt->sending, "xprt_sending"); | |
947 | rpc_init_wait_queue(&xprt->resend, "xprt_resend"); | |
948 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); | |
949 | ||
950 | /* initialize free list */ | |
951 | for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) | |
952 | list_add(&req->rq_list, &xprt->free); | |
953 | ||
954 | xprt_init_xid(xprt); | |
955 | ||
46121cf7 | 956 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 CL |
957 | xprt->max_reqs); |
958 | ||
959 | return xprt; | |
960 | } | |
961 | ||
9903cd1c CL |
962 | /** |
963 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
6b6ca86b | 964 | * @kref: kref for the transport to destroy |
9903cd1c | 965 | * |
1da177e4 | 966 | */ |
6b6ca86b | 967 | static void xprt_destroy(struct kref *kref) |
1da177e4 | 968 | { |
6b6ca86b TM |
969 | struct rpc_xprt *xprt = container_of(kref, struct rpc_xprt, kref); |
970 | ||
46121cf7 | 971 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 TM |
972 | xprt->shutdown = 1; |
973 | del_timer_sync(&xprt->timer); | |
c8541ecd CL |
974 | |
975 | /* | |
976 | * Tear down transport state and free the rpc_xprt | |
977 | */ | |
a246b010 | 978 | xprt->ops->destroy(xprt); |
6b6ca86b | 979 | } |
1da177e4 | 980 | |
6b6ca86b TM |
981 | /** |
982 | * xprt_put - release a reference to an RPC transport. | |
983 | * @xprt: pointer to the transport | |
984 | * | |
985 | */ | |
986 | void xprt_put(struct rpc_xprt *xprt) | |
987 | { | |
988 | kref_put(&xprt->kref, xprt_destroy); | |
989 | } | |
990 | ||
991 | /** | |
992 | * xprt_get - return a reference to an RPC transport. | |
993 | * @xprt: pointer to the transport | |
994 | * | |
995 | */ | |
996 | struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) | |
997 | { | |
998 | kref_get(&xprt->kref); | |
999 | return xprt; | |
1da177e4 | 1000 | } |