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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 | |
55ae1aab RL |
15 | * 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. | |
1da177e4 | 18 | * - When a packet arrives, the data_ready handler walks the list of |
55aa4f58 | 19 | * pending requests for that transport. If a matching XID is found, the |
1da177e4 LT |
20 | * 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> | |
55aa4f58 CL |
36 | * |
37 | * Transport switch API copyright (C) 2005, Chuck Lever <cel@netapp.com> | |
1da177e4 LT |
38 | */ |
39 | ||
a246b010 CL |
40 | #include <linux/module.h> |
41 | ||
1da177e4 | 42 | #include <linux/types.h> |
a246b010 | 43 | #include <linux/interrupt.h> |
1da177e4 | 44 | #include <linux/workqueue.h> |
bf3fcf89 | 45 | #include <linux/net.h> |
1da177e4 | 46 | |
a246b010 | 47 | #include <linux/sunrpc/clnt.h> |
11c556b3 | 48 | #include <linux/sunrpc/metrics.h> |
1da177e4 | 49 | |
55ae1aab RL |
50 | #include "sunrpc.h" |
51 | ||
1da177e4 LT |
52 | /* |
53 | * Local variables | |
54 | */ | |
55 | ||
56 | #ifdef RPC_DEBUG | |
1da177e4 LT |
57 | # define RPCDBG_FACILITY RPCDBG_XPRT |
58 | #endif | |
59 | ||
1da177e4 LT |
60 | /* |
61 | * Local functions | |
62 | */ | |
63 | static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); | |
64 | static inline void do_xprt_reserve(struct rpc_task *); | |
1da177e4 | 65 | static void xprt_connect_status(struct rpc_task *task); |
1da177e4 LT |
66 | static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
67 | ||
5ba03e82 | 68 | static DEFINE_SPINLOCK(xprt_list_lock); |
81c098af TT |
69 | static LIST_HEAD(xprt_list); |
70 | ||
555ee3af CL |
71 | /* |
72 | * The transport code maintains an estimate on the maximum number of out- | |
73 | * standing RPC requests, using a smoothed version of the congestion | |
74 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
75 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
76 | * halved; otherwise, it is incremented by 1/cwnd when | |
77 | * | |
78 | * - a reply is received and | |
79 | * - a full number of requests are outstanding and | |
80 | * - the congestion window hasn't been updated recently. | |
81 | */ | |
82 | #define RPC_CWNDSHIFT (8U) | |
83 | #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) | |
84 | #define RPC_INITCWND RPC_CWNDSCALE | |
85 | #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) | |
86 | ||
87 | #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) | |
1da177e4 | 88 | |
81c098af TT |
89 | /** |
90 | * xprt_register_transport - register a transport implementation | |
91 | * @transport: transport to register | |
92 | * | |
93 | * If a transport implementation is loaded as a kernel module, it can | |
94 | * call this interface to make itself known to the RPC client. | |
95 | * | |
96 | * Returns: | |
97 | * 0: transport successfully registered | |
98 | * -EEXIST: transport already registered | |
99 | * -EINVAL: transport module being unloaded | |
100 | */ | |
101 | int xprt_register_transport(struct xprt_class *transport) | |
102 | { | |
103 | struct xprt_class *t; | |
104 | int result; | |
105 | ||
106 | result = -EEXIST; | |
107 | spin_lock(&xprt_list_lock); | |
108 | list_for_each_entry(t, &xprt_list, list) { | |
109 | /* don't register the same transport class twice */ | |
4fa016eb | 110 | if (t->ident == transport->ident) |
81c098af TT |
111 | goto out; |
112 | } | |
113 | ||
c9f6cde6 DL |
114 | list_add_tail(&transport->list, &xprt_list); |
115 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
116 | transport->name); | |
117 | result = 0; | |
81c098af TT |
118 | |
119 | out: | |
120 | spin_unlock(&xprt_list_lock); | |
121 | return result; | |
122 | } | |
123 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
124 | ||
125 | /** | |
126 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 127 | * @transport: transport to unregister |
81c098af TT |
128 | * |
129 | * Returns: | |
130 | * 0: transport successfully unregistered | |
131 | * -ENOENT: transport never registered | |
132 | */ | |
133 | int xprt_unregister_transport(struct xprt_class *transport) | |
134 | { | |
135 | struct xprt_class *t; | |
136 | int result; | |
137 | ||
138 | result = 0; | |
139 | spin_lock(&xprt_list_lock); | |
140 | list_for_each_entry(t, &xprt_list, list) { | |
141 | if (t == transport) { | |
142 | printk(KERN_INFO | |
143 | "RPC: Unregistered %s transport module.\n", | |
144 | transport->name); | |
145 | list_del_init(&transport->list); | |
81c098af TT |
146 | goto out; |
147 | } | |
148 | } | |
149 | result = -ENOENT; | |
150 | ||
151 | out: | |
152 | spin_unlock(&xprt_list_lock); | |
153 | return result; | |
154 | } | |
155 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
156 | ||
441e3e24 TT |
157 | /** |
158 | * xprt_load_transport - load a transport implementation | |
159 | * @transport_name: transport to load | |
160 | * | |
161 | * Returns: | |
162 | * 0: transport successfully loaded | |
163 | * -ENOENT: transport module not available | |
164 | */ | |
165 | int xprt_load_transport(const char *transport_name) | |
166 | { | |
167 | struct xprt_class *t; | |
168 | char module_name[sizeof t->name + 5]; | |
169 | int result; | |
170 | ||
171 | result = 0; | |
172 | spin_lock(&xprt_list_lock); | |
173 | list_for_each_entry(t, &xprt_list, list) { | |
174 | if (strcmp(t->name, transport_name) == 0) { | |
175 | spin_unlock(&xprt_list_lock); | |
176 | goto out; | |
177 | } | |
178 | } | |
179 | spin_unlock(&xprt_list_lock); | |
180 | strcpy(module_name, "xprt"); | |
181 | strncat(module_name, transport_name, sizeof t->name); | |
182 | result = request_module(module_name); | |
183 | out: | |
184 | return result; | |
185 | } | |
186 | EXPORT_SYMBOL_GPL(xprt_load_transport); | |
187 | ||
12a80469 CL |
188 | /** |
189 | * xprt_reserve_xprt - serialize write access to transports | |
190 | * @task: task that is requesting access to the transport | |
191 | * | |
192 | * This prevents mixing the payload of separate requests, and prevents | |
193 | * transport connects from colliding with writes. No congestion control | |
194 | * is provided. | |
195 | */ | |
196 | int xprt_reserve_xprt(struct rpc_task *task) | |
197 | { | |
12a80469 | 198 | struct rpc_rqst *req = task->tk_rqstp; |
343952fa | 199 | struct rpc_xprt *xprt = req->rq_xprt; |
12a80469 CL |
200 | |
201 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
202 | if (task == xprt->snd_task) | |
203 | return 1; | |
204 | if (task == NULL) | |
205 | return 0; | |
206 | goto out_sleep; | |
207 | } | |
208 | xprt->snd_task = task; | |
209 | if (req) { | |
210 | req->rq_bytes_sent = 0; | |
211 | req->rq_ntrans++; | |
212 | } | |
213 | return 1; | |
214 | ||
215 | out_sleep: | |
46121cf7 | 216 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
217 | task->tk_pid, xprt); |
218 | task->tk_timeout = 0; | |
219 | task->tk_status = -EAGAIN; | |
220 | if (req && req->rq_ntrans) | |
5d00837b | 221 | rpc_sleep_on(&xprt->resend, task, NULL); |
12a80469 | 222 | else |
5d00837b | 223 | rpc_sleep_on(&xprt->sending, task, NULL); |
12a80469 CL |
224 | return 0; |
225 | } | |
12444809 | 226 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 227 | |
632e3bdc TM |
228 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
229 | { | |
230 | xprt->snd_task = NULL; | |
231 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { | |
232 | smp_mb__before_clear_bit(); | |
233 | clear_bit(XPRT_LOCKED, &xprt->state); | |
234 | smp_mb__after_clear_bit(); | |
235 | } else | |
c1384c9c | 236 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
237 | } |
238 | ||
1da177e4 | 239 | /* |
12a80469 CL |
240 | * xprt_reserve_xprt_cong - serialize write access to transports |
241 | * @task: task that is requesting access to the transport | |
242 | * | |
243 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
244 | * integrated into the decision of whether a request is allowed to be | |
245 | * woken up and given access to the transport. | |
1da177e4 | 246 | */ |
12a80469 | 247 | int xprt_reserve_xprt_cong(struct rpc_task *task) |
1da177e4 | 248 | { |
12a80469 | 249 | struct rpc_xprt *xprt = task->tk_xprt; |
1da177e4 LT |
250 | struct rpc_rqst *req = task->tk_rqstp; |
251 | ||
2226feb6 | 252 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
253 | if (task == xprt->snd_task) |
254 | return 1; | |
1da177e4 LT |
255 | goto out_sleep; |
256 | } | |
12a80469 | 257 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
258 | xprt->snd_task = task; |
259 | if (req) { | |
260 | req->rq_bytes_sent = 0; | |
261 | req->rq_ntrans++; | |
262 | } | |
263 | return 1; | |
264 | } | |
632e3bdc | 265 | xprt_clear_locked(xprt); |
1da177e4 | 266 | out_sleep: |
46121cf7 | 267 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
268 | task->tk_timeout = 0; |
269 | task->tk_status = -EAGAIN; | |
270 | if (req && req->rq_ntrans) | |
5d00837b | 271 | rpc_sleep_on(&xprt->resend, task, NULL); |
1da177e4 | 272 | else |
5d00837b | 273 | rpc_sleep_on(&xprt->sending, task, NULL); |
1da177e4 LT |
274 | return 0; |
275 | } | |
12444809 | 276 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 277 | |
12a80469 | 278 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
279 | { |
280 | int retval; | |
281 | ||
4a0f8c04 | 282 | spin_lock_bh(&xprt->transport_lock); |
12a80469 | 283 | retval = xprt->ops->reserve_xprt(task); |
4a0f8c04 | 284 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
285 | return retval; |
286 | } | |
287 | ||
12a80469 | 288 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
49e9a890 CL |
289 | { |
290 | struct rpc_task *task; | |
291 | struct rpc_rqst *req; | |
292 | ||
293 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
294 | return; | |
295 | ||
296 | task = rpc_wake_up_next(&xprt->resend); | |
297 | if (!task) { | |
298 | task = rpc_wake_up_next(&xprt->sending); | |
299 | if (!task) | |
300 | goto out_unlock; | |
301 | } | |
302 | ||
303 | req = task->tk_rqstp; | |
304 | xprt->snd_task = task; | |
305 | if (req) { | |
306 | req->rq_bytes_sent = 0; | |
307 | req->rq_ntrans++; | |
308 | } | |
309 | return; | |
310 | ||
311 | out_unlock: | |
632e3bdc | 312 | xprt_clear_locked(xprt); |
49e9a890 CL |
313 | } |
314 | ||
315 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
1da177e4 LT |
316 | { |
317 | struct rpc_task *task; | |
318 | ||
2226feb6 | 319 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 320 | return; |
49e9a890 | 321 | if (RPCXPRT_CONGESTED(xprt)) |
1da177e4 LT |
322 | goto out_unlock; |
323 | task = rpc_wake_up_next(&xprt->resend); | |
324 | if (!task) { | |
325 | task = rpc_wake_up_next(&xprt->sending); | |
326 | if (!task) | |
327 | goto out_unlock; | |
328 | } | |
49e9a890 | 329 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
330 | struct rpc_rqst *req = task->tk_rqstp; |
331 | xprt->snd_task = task; | |
332 | if (req) { | |
333 | req->rq_bytes_sent = 0; | |
334 | req->rq_ntrans++; | |
335 | } | |
336 | return; | |
337 | } | |
338 | out_unlock: | |
632e3bdc | 339 | xprt_clear_locked(xprt); |
1da177e4 LT |
340 | } |
341 | ||
49e9a890 CL |
342 | /** |
343 | * xprt_release_xprt - allow other requests to use a transport | |
344 | * @xprt: transport with other tasks potentially waiting | |
345 | * @task: task that is releasing access to the transport | |
346 | * | |
347 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 348 | */ |
49e9a890 | 349 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
350 | { |
351 | if (xprt->snd_task == task) { | |
632e3bdc | 352 | xprt_clear_locked(xprt); |
1da177e4 LT |
353 | __xprt_lock_write_next(xprt); |
354 | } | |
355 | } | |
12444809 | 356 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 357 | |
49e9a890 CL |
358 | /** |
359 | * xprt_release_xprt_cong - allow other requests to use a transport | |
360 | * @xprt: transport with other tasks potentially waiting | |
361 | * @task: task that is releasing access to the transport | |
362 | * | |
363 | * Note that "task" can be NULL. Another task is awoken to use the | |
364 | * transport if the transport's congestion window allows it. | |
365 | */ | |
366 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
367 | { | |
368 | if (xprt->snd_task == task) { | |
632e3bdc | 369 | xprt_clear_locked(xprt); |
49e9a890 CL |
370 | __xprt_lock_write_next_cong(xprt); |
371 | } | |
372 | } | |
12444809 | 373 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
374 | |
375 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 376 | { |
4a0f8c04 | 377 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 378 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 379 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
380 | } |
381 | ||
1da177e4 LT |
382 | /* |
383 | * Van Jacobson congestion avoidance. Check if the congestion window | |
384 | * overflowed. Put the task to sleep if this is the case. | |
385 | */ | |
386 | static int | |
387 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
388 | { | |
389 | struct rpc_rqst *req = task->tk_rqstp; | |
390 | ||
391 | if (req->rq_cong) | |
392 | return 1; | |
46121cf7 | 393 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
394 | task->tk_pid, xprt->cong, xprt->cwnd); |
395 | if (RPCXPRT_CONGESTED(xprt)) | |
396 | return 0; | |
397 | req->rq_cong = 1; | |
398 | xprt->cong += RPC_CWNDSCALE; | |
399 | return 1; | |
400 | } | |
401 | ||
402 | /* | |
403 | * Adjust the congestion window, and wake up the next task | |
404 | * that has been sleeping due to congestion | |
405 | */ | |
406 | static void | |
407 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
408 | { | |
409 | if (!req->rq_cong) | |
410 | return; | |
411 | req->rq_cong = 0; | |
412 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 413 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
414 | } |
415 | ||
a58dd398 CL |
416 | /** |
417 | * xprt_release_rqst_cong - housekeeping when request is complete | |
418 | * @task: RPC request that recently completed | |
419 | * | |
420 | * Useful for transports that require congestion control. | |
421 | */ | |
422 | void xprt_release_rqst_cong(struct rpc_task *task) | |
423 | { | |
424 | __xprt_put_cong(task->tk_xprt, task->tk_rqstp); | |
425 | } | |
12444809 | 426 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 427 | |
46c0ee8b CL |
428 | /** |
429 | * xprt_adjust_cwnd - adjust transport congestion window | |
430 | * @task: recently completed RPC request used to adjust window | |
431 | * @result: result code of completed RPC request | |
432 | * | |
1da177e4 LT |
433 | * We use a time-smoothed congestion estimator to avoid heavy oscillation. |
434 | */ | |
46c0ee8b | 435 | void xprt_adjust_cwnd(struct rpc_task *task, int result) |
1da177e4 | 436 | { |
46c0ee8b CL |
437 | struct rpc_rqst *req = task->tk_rqstp; |
438 | struct rpc_xprt *xprt = task->tk_xprt; | |
439 | unsigned long cwnd = xprt->cwnd; | |
1da177e4 | 440 | |
1da177e4 LT |
441 | if (result >= 0 && cwnd <= xprt->cong) { |
442 | /* The (cwnd >> 1) term makes sure | |
443 | * the result gets rounded properly. */ | |
444 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
445 | if (cwnd > RPC_MAXCWND(xprt)) | |
446 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 447 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
448 | } else if (result == -ETIMEDOUT) { |
449 | cwnd >>= 1; | |
450 | if (cwnd < RPC_CWNDSCALE) | |
451 | cwnd = RPC_CWNDSCALE; | |
452 | } | |
46121cf7 | 453 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
454 | xprt->cong, xprt->cwnd, cwnd); |
455 | xprt->cwnd = cwnd; | |
46c0ee8b | 456 | __xprt_put_cong(xprt, req); |
1da177e4 | 457 | } |
12444809 | 458 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 459 | |
44fbac22 CL |
460 | /** |
461 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
462 | * @xprt: transport with waiting tasks | |
463 | * @status: result code to plant in each task before waking it | |
464 | * | |
465 | */ | |
466 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
467 | { | |
468 | if (status < 0) | |
469 | rpc_wake_up_status(&xprt->pending, status); | |
470 | else | |
471 | rpc_wake_up(&xprt->pending); | |
472 | } | |
12444809 | 473 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 474 | |
c7b2cae8 CL |
475 | /** |
476 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
477 | * @task: task to be put to sleep | |
0b80ae42 | 478 | * @action: function pointer to be executed after wait |
c7b2cae8 | 479 | */ |
b6ddf64f | 480 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
481 | { |
482 | struct rpc_rqst *req = task->tk_rqstp; | |
483 | struct rpc_xprt *xprt = req->rq_xprt; | |
484 | ||
485 | task->tk_timeout = req->rq_timeout; | |
b6ddf64f | 486 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 487 | } |
12444809 | 488 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
489 | |
490 | /** | |
491 | * xprt_write_space - wake the task waiting for transport output buffer space | |
492 | * @xprt: transport with waiting tasks | |
493 | * | |
494 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
495 | */ | |
496 | void xprt_write_space(struct rpc_xprt *xprt) | |
497 | { | |
498 | if (unlikely(xprt->shutdown)) | |
499 | return; | |
500 | ||
501 | spin_lock_bh(&xprt->transport_lock); | |
502 | if (xprt->snd_task) { | |
46121cf7 CL |
503 | dprintk("RPC: write space: waking waiting task on " |
504 | "xprt %p\n", xprt); | |
fda13939 | 505 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
506 | } |
507 | spin_unlock_bh(&xprt->transport_lock); | |
508 | } | |
12444809 | 509 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 510 | |
fe3aca29 CL |
511 | /** |
512 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
513 | * @task: task whose timeout is to be set | |
514 | * | |
515 | * Set a request's retransmit timeout based on the transport's | |
516 | * default timeout parameters. Used by transports that don't adjust | |
517 | * the retransmit timeout based on round-trip time estimation. | |
518 | */ | |
519 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
520 | { | |
521 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
522 | } | |
12444809 | 523 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 CL |
524 | |
525 | /* | |
526 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout | |
527 | * @task: task whose timeout is to be set | |
cca5172a | 528 | * |
fe3aca29 CL |
529 | * Set a request's retransmit timeout using the RTT estimator. |
530 | */ | |
531 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
532 | { | |
533 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
534 | struct rpc_clnt *clnt = task->tk_client; |
535 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 536 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 537 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
538 | |
539 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
540 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
541 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
542 | task->tk_timeout = max_timeout; | |
543 | } | |
12444809 | 544 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 545 | |
1da177e4 LT |
546 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
547 | { | |
ba7392bb | 548 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
549 | |
550 | req->rq_majortimeo = req->rq_timeout; | |
551 | if (to->to_exponential) | |
552 | req->rq_majortimeo <<= to->to_retries; | |
553 | else | |
554 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
555 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
556 | req->rq_majortimeo = to->to_maxval; | |
557 | req->rq_majortimeo += jiffies; | |
558 | } | |
559 | ||
9903cd1c CL |
560 | /** |
561 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
562 | * @req: RPC request containing parameters to use for the adjustment | |
563 | * | |
1da177e4 LT |
564 | */ |
565 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
566 | { | |
567 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 568 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
569 | int status = 0; |
570 | ||
571 | if (time_before(jiffies, req->rq_majortimeo)) { | |
572 | if (to->to_exponential) | |
573 | req->rq_timeout <<= 1; | |
574 | else | |
575 | req->rq_timeout += to->to_increment; | |
576 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
577 | req->rq_timeout = to->to_maxval; | |
578 | req->rq_retries++; | |
1da177e4 LT |
579 | } else { |
580 | req->rq_timeout = to->to_initval; | |
581 | req->rq_retries = 0; | |
582 | xprt_reset_majortimeo(req); | |
583 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 584 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 585 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 586 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
587 | status = -ETIMEDOUT; |
588 | } | |
589 | ||
590 | if (req->rq_timeout == 0) { | |
591 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
592 | req->rq_timeout = 5 * HZ; | |
593 | } | |
594 | return status; | |
595 | } | |
596 | ||
65f27f38 | 597 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 598 | { |
65f27f38 DH |
599 | struct rpc_xprt *xprt = |
600 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 601 | |
a246b010 | 602 | xprt->ops->close(xprt); |
66af1e55 | 603 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
1da177e4 LT |
604 | xprt_release_write(xprt, NULL); |
605 | } | |
606 | ||
9903cd1c | 607 | /** |
62da3b24 | 608 | * xprt_disconnect_done - mark a transport as disconnected |
9903cd1c CL |
609 | * @xprt: transport to flag for disconnect |
610 | * | |
1da177e4 | 611 | */ |
62da3b24 | 612 | void xprt_disconnect_done(struct rpc_xprt *xprt) |
1da177e4 | 613 | { |
46121cf7 | 614 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 615 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 616 | xprt_clear_connected(xprt); |
2a491991 | 617 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
4a0f8c04 | 618 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 619 | } |
62da3b24 | 620 | EXPORT_SYMBOL_GPL(xprt_disconnect_done); |
1da177e4 | 621 | |
66af1e55 TM |
622 | /** |
623 | * xprt_force_disconnect - force a transport to disconnect | |
624 | * @xprt: transport to disconnect | |
625 | * | |
626 | */ | |
627 | void xprt_force_disconnect(struct rpc_xprt *xprt) | |
628 | { | |
629 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
630 | spin_lock_bh(&xprt->transport_lock); | |
631 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
632 | /* Try to schedule an autoclose RPC call */ | |
633 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
634 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 635 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
66af1e55 TM |
636 | spin_unlock_bh(&xprt->transport_lock); |
637 | } | |
66af1e55 | 638 | |
7c1d71cf TM |
639 | /** |
640 | * xprt_conditional_disconnect - force a transport to disconnect | |
641 | * @xprt: transport to disconnect | |
642 | * @cookie: 'connection cookie' | |
643 | * | |
644 | * This attempts to break the connection if and only if 'cookie' matches | |
645 | * the current transport 'connection cookie'. It ensures that we don't | |
646 | * try to break the connection more than once when we need to retransmit | |
647 | * a batch of RPC requests. | |
648 | * | |
649 | */ | |
650 | void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) | |
651 | { | |
652 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
653 | spin_lock_bh(&xprt->transport_lock); | |
654 | if (cookie != xprt->connect_cookie) | |
655 | goto out; | |
656 | if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) | |
657 | goto out; | |
658 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
659 | /* Try to schedule an autoclose RPC call */ | |
660 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
661 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 662 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
7c1d71cf TM |
663 | out: |
664 | spin_unlock_bh(&xprt->transport_lock); | |
665 | } | |
666 | ||
1da177e4 LT |
667 | static void |
668 | xprt_init_autodisconnect(unsigned long data) | |
669 | { | |
670 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
671 | ||
4a0f8c04 | 672 | spin_lock(&xprt->transport_lock); |
1da177e4 LT |
673 | if (!list_empty(&xprt->recv) || xprt->shutdown) |
674 | goto out_abort; | |
2226feb6 | 675 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 676 | goto out_abort; |
4a0f8c04 | 677 | spin_unlock(&xprt->transport_lock); |
f75e6745 TM |
678 | set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); |
679 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
1da177e4 LT |
680 | return; |
681 | out_abort: | |
4a0f8c04 | 682 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
683 | } |
684 | ||
9903cd1c CL |
685 | /** |
686 | * xprt_connect - schedule a transport connect operation | |
687 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
688 | * |
689 | */ | |
690 | void xprt_connect(struct rpc_task *task) | |
691 | { | |
692 | struct rpc_xprt *xprt = task->tk_xprt; | |
693 | ||
46121cf7 | 694 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
695 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
696 | ||
ec739ef0 | 697 | if (!xprt_bound(xprt)) { |
01d37c42 | 698 | task->tk_status = -EAGAIN; |
1da177e4 LT |
699 | return; |
700 | } | |
701 | if (!xprt_lock_write(xprt, task)) | |
702 | return; | |
feb8ca37 TM |
703 | |
704 | if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) | |
705 | xprt->ops->close(xprt); | |
706 | ||
1da177e4 | 707 | if (xprt_connected(xprt)) |
a246b010 CL |
708 | xprt_release_write(xprt, task); |
709 | else { | |
710 | if (task->tk_rqstp) | |
711 | task->tk_rqstp->rq_bytes_sent = 0; | |
1da177e4 | 712 | |
03bf4b70 | 713 | task->tk_timeout = xprt->connect_timeout; |
5d00837b | 714 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
262ca07d | 715 | xprt->stat.connect_start = jiffies; |
a246b010 | 716 | xprt->ops->connect(task); |
1da177e4 LT |
717 | } |
718 | return; | |
1da177e4 LT |
719 | } |
720 | ||
9903cd1c | 721 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 LT |
722 | { |
723 | struct rpc_xprt *xprt = task->tk_xprt; | |
724 | ||
cd983ef8 | 725 | if (task->tk_status == 0) { |
262ca07d CL |
726 | xprt->stat.connect_count++; |
727 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 728 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
729 | task->tk_pid); |
730 | return; | |
731 | } | |
732 | ||
1da177e4 | 733 | switch (task->tk_status) { |
2a491991 TM |
734 | case -EAGAIN: |
735 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 736 | break; |
1da177e4 | 737 | case -ETIMEDOUT: |
46121cf7 CL |
738 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
739 | "out\n", task->tk_pid); | |
1da177e4 LT |
740 | break; |
741 | default: | |
46121cf7 CL |
742 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
743 | "server %s\n", task->tk_pid, -task->tk_status, | |
744 | task->tk_client->cl_server); | |
23475d66 CL |
745 | xprt_release_write(xprt, task); |
746 | task->tk_status = -EIO; | |
1da177e4 | 747 | } |
1da177e4 LT |
748 | } |
749 | ||
9903cd1c CL |
750 | /** |
751 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
752 | * @xprt: transport on which the original request was transmitted | |
753 | * @xid: RPC XID of incoming reply | |
754 | * | |
1da177e4 | 755 | */ |
d8ed029d | 756 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 LT |
757 | { |
758 | struct list_head *pos; | |
1da177e4 LT |
759 | |
760 | list_for_each(pos, &xprt->recv) { | |
761 | struct rpc_rqst *entry = list_entry(pos, struct rpc_rqst, rq_list); | |
262ca07d CL |
762 | if (entry->rq_xid == xid) |
763 | return entry; | |
1da177e4 | 764 | } |
46121cf7 CL |
765 | |
766 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
767 | ntohl(xid)); | |
262ca07d CL |
768 | xprt->stat.bad_xids++; |
769 | return NULL; | |
1da177e4 | 770 | } |
12444809 | 771 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 772 | |
1570c1e4 CL |
773 | /** |
774 | * xprt_update_rtt - update an RPC client's RTT state after receiving a reply | |
775 | * @task: RPC request that recently completed | |
776 | * | |
777 | */ | |
778 | void xprt_update_rtt(struct rpc_task *task) | |
779 | { | |
780 | struct rpc_rqst *req = task->tk_rqstp; | |
781 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
782 | unsigned timer = task->tk_msg.rpc_proc->p_timer; | |
783 | ||
784 | if (timer) { | |
785 | if (req->rq_ntrans == 1) | |
786 | rpc_update_rtt(rtt, timer, | |
787 | (long)jiffies - req->rq_xtime); | |
788 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); | |
789 | } | |
790 | } | |
12444809 | 791 | EXPORT_SYMBOL_GPL(xprt_update_rtt); |
1570c1e4 | 792 | |
9903cd1c CL |
793 | /** |
794 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 795 | * @task: RPC request that recently completed |
9903cd1c CL |
796 | * @copied: actual number of bytes received from the transport |
797 | * | |
1570c1e4 | 798 | * Caller holds transport lock. |
1da177e4 | 799 | */ |
1570c1e4 | 800 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 801 | { |
1570c1e4 | 802 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 803 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 804 | |
1570c1e4 CL |
805 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
806 | task->tk_pid, ntohl(req->rq_xid), copied); | |
1da177e4 | 807 | |
fda13939 | 808 | xprt->stat.recvs++; |
ef759a2e CL |
809 | task->tk_rtt = (long)jiffies - req->rq_xtime; |
810 | ||
1da177e4 | 811 | list_del_init(&req->rq_list); |
1e799b67 | 812 | req->rq_private_buf.len = copied; |
dd2b63d0 RL |
813 | /* Ensure all writes are done before we update */ |
814 | /* req->rq_reply_bytes_recvd */ | |
43ac3f29 | 815 | smp_wmb(); |
dd2b63d0 | 816 | req->rq_reply_bytes_recvd = copied; |
fda13939 | 817 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 818 | } |
12444809 | 819 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 820 | |
46c0ee8b | 821 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 822 | { |
46c0ee8b | 823 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
824 | struct rpc_xprt *xprt = req->rq_xprt; |
825 | ||
5d00837b TM |
826 | if (task->tk_status != -ETIMEDOUT) |
827 | return; | |
46121cf7 | 828 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 829 | |
5d00837b | 830 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 | 831 | if (!req->rq_reply_bytes_recvd) { |
46c0ee8b CL |
832 | if (xprt->ops->timer) |
833 | xprt->ops->timer(task); | |
5d00837b TM |
834 | } else |
835 | task->tk_status = 0; | |
836 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
837 | } |
838 | ||
4cfc7e60 RI |
839 | static inline int xprt_has_timer(struct rpc_xprt *xprt) |
840 | { | |
841 | return xprt->idle_timeout != 0; | |
842 | } | |
843 | ||
9903cd1c CL |
844 | /** |
845 | * xprt_prepare_transmit - reserve the transport before sending a request | |
846 | * @task: RPC task about to send a request | |
847 | * | |
1da177e4 | 848 | */ |
9903cd1c | 849 | int xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
850 | { |
851 | struct rpc_rqst *req = task->tk_rqstp; | |
852 | struct rpc_xprt *xprt = req->rq_xprt; | |
853 | int err = 0; | |
854 | ||
46121cf7 | 855 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 856 | |
4a0f8c04 | 857 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 RL |
858 | if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) { |
859 | err = req->rq_reply_bytes_recvd; | |
1da177e4 LT |
860 | goto out_unlock; |
861 | } | |
2a491991 | 862 | if (!xprt->ops->reserve_xprt(task)) |
1da177e4 | 863 | err = -EAGAIN; |
1da177e4 | 864 | out_unlock: |
4a0f8c04 | 865 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
866 | return err; |
867 | } | |
868 | ||
e0ab53de | 869 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 870 | { |
343952fa | 871 | xprt_release_write(task->tk_rqstp->rq_xprt, task); |
5e5ce5be TM |
872 | } |
873 | ||
9903cd1c CL |
874 | /** |
875 | * xprt_transmit - send an RPC request on a transport | |
876 | * @task: controlling RPC task | |
877 | * | |
878 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
879 | */ | |
880 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 881 | { |
1da177e4 LT |
882 | struct rpc_rqst *req = task->tk_rqstp; |
883 | struct rpc_xprt *xprt = req->rq_xprt; | |
a246b010 | 884 | int status; |
1da177e4 | 885 | |
46121cf7 | 886 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 887 | |
dd2b63d0 | 888 | if (!req->rq_reply_bytes_recvd) { |
55ae1aab RL |
889 | if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { |
890 | /* | |
891 | * Add to the list only if we're expecting a reply | |
892 | */ | |
4a0f8c04 | 893 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
894 | /* Update the softirq receive buffer */ |
895 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
896 | sizeof(req->rq_private_buf)); | |
897 | /* Add request to the receive list */ | |
898 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 899 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 900 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
901 | /* Turn off autodisconnect */ |
902 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
903 | } |
904 | } else if (!req->rq_bytes_sent) | |
905 | return; | |
906 | ||
7c1d71cf | 907 | req->rq_connect_cookie = xprt->connect_cookie; |
b22602a6 | 908 | req->rq_xtime = jiffies; |
a246b010 | 909 | status = xprt->ops->send_request(task); |
c8485e4d TM |
910 | if (status != 0) { |
911 | task->tk_status = status; | |
912 | return; | |
913 | } | |
262ca07d | 914 | |
c8485e4d TM |
915 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
916 | spin_lock_bh(&xprt->transport_lock); | |
262ca07d | 917 | |
c8485e4d | 918 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 919 | |
c8485e4d TM |
920 | xprt->stat.sends++; |
921 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
922 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
1da177e4 | 923 | |
c8485e4d TM |
924 | /* Don't race with disconnect */ |
925 | if (!xprt_connected(xprt)) | |
926 | task->tk_status = -ENOTCONN; | |
dd2b63d0 | 927 | else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) { |
55ae1aab RL |
928 | /* |
929 | * Sleep on the pending queue since | |
930 | * we're expecting a reply. | |
931 | */ | |
c8485e4d | 932 | rpc_sleep_on(&xprt->pending, task, xprt_timer); |
55ae1aab | 933 | } |
c8485e4d | 934 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
935 | } |
936 | ||
9903cd1c | 937 | static inline void do_xprt_reserve(struct rpc_task *task) |
1da177e4 LT |
938 | { |
939 | struct rpc_xprt *xprt = task->tk_xprt; | |
940 | ||
941 | task->tk_status = 0; | |
942 | if (task->tk_rqstp) | |
943 | return; | |
944 | if (!list_empty(&xprt->free)) { | |
945 | struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); | |
946 | list_del_init(&req->rq_list); | |
947 | task->tk_rqstp = req; | |
948 | xprt_request_init(task, xprt); | |
949 | return; | |
950 | } | |
46121cf7 | 951 | dprintk("RPC: waiting for request slot\n"); |
1da177e4 LT |
952 | task->tk_status = -EAGAIN; |
953 | task->tk_timeout = 0; | |
5d00837b | 954 | rpc_sleep_on(&xprt->backlog, task, NULL); |
1da177e4 LT |
955 | } |
956 | ||
9903cd1c CL |
957 | /** |
958 | * xprt_reserve - allocate an RPC request slot | |
959 | * @task: RPC task requesting a slot allocation | |
960 | * | |
961 | * If no more slots are available, place the task on the transport's | |
962 | * backlog queue. | |
963 | */ | |
964 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 LT |
965 | { |
966 | struct rpc_xprt *xprt = task->tk_xprt; | |
967 | ||
968 | task->tk_status = -EIO; | |
0065db32 TM |
969 | spin_lock(&xprt->reserve_lock); |
970 | do_xprt_reserve(task); | |
971 | spin_unlock(&xprt->reserve_lock); | |
1da177e4 LT |
972 | } |
973 | ||
d8ed029d | 974 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 LT |
975 | { |
976 | return xprt->xid++; | |
977 | } | |
978 | ||
979 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
980 | { | |
bf3fcf89 | 981 | xprt->xid = net_random(); |
1da177e4 LT |
982 | } |
983 | ||
9903cd1c | 984 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
985 | { |
986 | struct rpc_rqst *req = task->tk_rqstp; | |
987 | ||
ba7392bb | 988 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
989 | req->rq_task = task; |
990 | req->rq_xprt = xprt; | |
02107148 | 991 | req->rq_buffer = NULL; |
1da177e4 | 992 | req->rq_xid = xprt_alloc_xid(xprt); |
ead5e1c2 | 993 | req->rq_release_snd_buf = NULL; |
da45828e | 994 | xprt_reset_majortimeo(req); |
46121cf7 | 995 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
996 | req, ntohl(req->rq_xid)); |
997 | } | |
998 | ||
9903cd1c CL |
999 | /** |
1000 | * xprt_release - release an RPC request slot | |
1001 | * @task: task which is finished with the slot | |
1002 | * | |
1da177e4 | 1003 | */ |
9903cd1c | 1004 | void xprt_release(struct rpc_task *task) |
1da177e4 | 1005 | { |
55ae1aab | 1006 | struct rpc_xprt *xprt; |
1da177e4 | 1007 | struct rpc_rqst *req; |
55ae1aab | 1008 | int is_bc_request; |
1da177e4 LT |
1009 | |
1010 | if (!(req = task->tk_rqstp)) | |
1011 | return; | |
55ae1aab RL |
1012 | |
1013 | /* Preallocated backchannel request? */ | |
1014 | is_bc_request = bc_prealloc(req); | |
1015 | ||
1016 | xprt = req->rq_xprt; | |
11c556b3 | 1017 | rpc_count_iostats(task); |
4a0f8c04 | 1018 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 1019 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
1020 | if (xprt->ops->release_request) |
1021 | xprt->ops->release_request(task); | |
1da177e4 LT |
1022 | if (!list_empty(&req->rq_list)) |
1023 | list_del(&req->rq_list); | |
1024 | xprt->last_used = jiffies; | |
4cfc7e60 | 1025 | if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) |
a246b010 | 1026 | mod_timer(&xprt->timer, |
03bf4b70 | 1027 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1028 | spin_unlock_bh(&xprt->transport_lock); |
55ae1aab RL |
1029 | if (!bc_prealloc(req)) |
1030 | xprt->ops->buf_free(req->rq_buffer); | |
1da177e4 | 1031 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1032 | if (req->rq_release_snd_buf) |
1033 | req->rq_release_snd_buf(req); | |
55ae1aab RL |
1034 | |
1035 | /* | |
1036 | * Early exit if this is a backchannel preallocated request. | |
1037 | * There is no need to have it added to the RPC slot list. | |
1038 | */ | |
1039 | if (is_bc_request) | |
1040 | return; | |
1041 | ||
1da177e4 LT |
1042 | memset(req, 0, sizeof(*req)); /* mark unused */ |
1043 | ||
46121cf7 | 1044 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
1da177e4 | 1045 | |
5dc07727 | 1046 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 1047 | list_add(&req->rq_list, &xprt->free); |
555ee3af | 1048 | rpc_wake_up_next(&xprt->backlog); |
5dc07727 | 1049 | spin_unlock(&xprt->reserve_lock); |
1da177e4 LT |
1050 | } |
1051 | ||
c2866763 CL |
1052 | /** |
1053 | * xprt_create_transport - create an RPC transport | |
96802a09 | 1054 | * @args: rpc transport creation arguments |
c2866763 CL |
1055 | * |
1056 | */ | |
3c341b0b | 1057 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) |
c2866763 | 1058 | { |
c2866763 CL |
1059 | struct rpc_xprt *xprt; |
1060 | struct rpc_rqst *req; | |
bc25571e | 1061 | struct xprt_class *t; |
c2866763 | 1062 | |
bc25571e TT |
1063 | spin_lock(&xprt_list_lock); |
1064 | list_for_each_entry(t, &xprt_list, list) { | |
4fa016eb | 1065 | if (t->ident == args->ident) { |
bc25571e TT |
1066 | spin_unlock(&xprt_list_lock); |
1067 | goto found; | |
1068 | } | |
c2866763 | 1069 | } |
bc25571e | 1070 | spin_unlock(&xprt_list_lock); |
4fa016eb | 1071 | printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); |
bc25571e TT |
1072 | return ERR_PTR(-EIO); |
1073 | ||
1074 | found: | |
1075 | xprt = t->setup(args); | |
c8541ecd | 1076 | if (IS_ERR(xprt)) { |
46121cf7 | 1077 | dprintk("RPC: xprt_create_transport: failed, %ld\n", |
c8541ecd CL |
1078 | -PTR_ERR(xprt)); |
1079 | return xprt; | |
c2866763 CL |
1080 | } |
1081 | ||
6b6ca86b | 1082 | kref_init(&xprt->kref); |
c2866763 CL |
1083 | spin_lock_init(&xprt->transport_lock); |
1084 | spin_lock_init(&xprt->reserve_lock); | |
1085 | ||
1086 | INIT_LIST_HEAD(&xprt->free); | |
1087 | INIT_LIST_HEAD(&xprt->recv); | |
f9acac1a RL |
1088 | #if defined(CONFIG_NFS_V4_1) |
1089 | spin_lock_init(&xprt->bc_pa_lock); | |
1090 | INIT_LIST_HEAD(&xprt->bc_pa_list); | |
1091 | #endif /* CONFIG_NFS_V4_1 */ | |
1092 | ||
65f27f38 | 1093 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
4cfc7e60 RI |
1094 | if (xprt_has_timer(xprt)) |
1095 | setup_timer(&xprt->timer, xprt_init_autodisconnect, | |
1096 | (unsigned long)xprt); | |
1097 | else | |
1098 | init_timer(&xprt->timer); | |
c2866763 CL |
1099 | xprt->last_used = jiffies; |
1100 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1101 | xprt->bind_index = 0; |
c2866763 CL |
1102 | |
1103 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1104 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
1105 | rpc_init_wait_queue(&xprt->sending, "xprt_sending"); | |
1106 | rpc_init_wait_queue(&xprt->resend, "xprt_resend"); | |
1107 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); | |
1108 | ||
1109 | /* initialize free list */ | |
1110 | for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) | |
1111 | list_add(&req->rq_list, &xprt->free); | |
1112 | ||
1113 | xprt_init_xid(xprt); | |
1114 | ||
46121cf7 | 1115 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 | 1116 | xprt->max_reqs); |
c2866763 CL |
1117 | return xprt; |
1118 | } | |
1119 | ||
9903cd1c CL |
1120 | /** |
1121 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
6b6ca86b | 1122 | * @kref: kref for the transport to destroy |
9903cd1c | 1123 | * |
1da177e4 | 1124 | */ |
6b6ca86b | 1125 | static void xprt_destroy(struct kref *kref) |
1da177e4 | 1126 | { |
6b6ca86b TM |
1127 | struct rpc_xprt *xprt = container_of(kref, struct rpc_xprt, kref); |
1128 | ||
46121cf7 | 1129 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 TM |
1130 | xprt->shutdown = 1; |
1131 | del_timer_sync(&xprt->timer); | |
c8541ecd | 1132 | |
f6a1cc89 TM |
1133 | rpc_destroy_wait_queue(&xprt->binding); |
1134 | rpc_destroy_wait_queue(&xprt->pending); | |
1135 | rpc_destroy_wait_queue(&xprt->sending); | |
1136 | rpc_destroy_wait_queue(&xprt->resend); | |
1137 | rpc_destroy_wait_queue(&xprt->backlog); | |
c8541ecd CL |
1138 | /* |
1139 | * Tear down transport state and free the rpc_xprt | |
1140 | */ | |
a246b010 | 1141 | xprt->ops->destroy(xprt); |
6b6ca86b | 1142 | } |
1da177e4 | 1143 | |
6b6ca86b TM |
1144 | /** |
1145 | * xprt_put - release a reference to an RPC transport. | |
1146 | * @xprt: pointer to the transport | |
1147 | * | |
1148 | */ | |
1149 | void xprt_put(struct rpc_xprt *xprt) | |
1150 | { | |
1151 | kref_put(&xprt->kref, xprt_destroy); | |
1152 | } | |
1153 | ||
1154 | /** | |
1155 | * xprt_get - return a reference to an RPC transport. | |
1156 | * @xprt: pointer to the transport | |
1157 | * | |
1158 | */ | |
1159 | struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) | |
1160 | { | |
1161 | kref_get(&xprt->kref); | |
1162 | return xprt; | |
1da177e4 | 1163 | } |