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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> |
ff839970 | 46 | #include <linux/ktime.h> |
1da177e4 | 47 | |
a246b010 | 48 | #include <linux/sunrpc/clnt.h> |
11c556b3 | 49 | #include <linux/sunrpc/metrics.h> |
c9acb42e | 50 | #include <linux/sunrpc/bc_xprt.h> |
1da177e4 | 51 | |
55ae1aab RL |
52 | #include "sunrpc.h" |
53 | ||
1da177e4 LT |
54 | /* |
55 | * Local variables | |
56 | */ | |
57 | ||
58 | #ifdef RPC_DEBUG | |
1da177e4 LT |
59 | # define RPCDBG_FACILITY RPCDBG_XPRT |
60 | #endif | |
61 | ||
1da177e4 LT |
62 | /* |
63 | * Local functions | |
64 | */ | |
65 | static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); | |
1da177e4 | 66 | static void xprt_connect_status(struct rpc_task *task); |
1da177e4 LT |
67 | static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
68 | ||
5ba03e82 | 69 | static DEFINE_SPINLOCK(xprt_list_lock); |
81c098af TT |
70 | static LIST_HEAD(xprt_list); |
71 | ||
555ee3af CL |
72 | /* |
73 | * The transport code maintains an estimate on the maximum number of out- | |
74 | * standing RPC requests, using a smoothed version of the congestion | |
75 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
76 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
77 | * halved; otherwise, it is incremented by 1/cwnd when | |
78 | * | |
79 | * - a reply is received and | |
80 | * - a full number of requests are outstanding and | |
81 | * - the congestion window hasn't been updated recently. | |
82 | */ | |
83 | #define RPC_CWNDSHIFT (8U) | |
84 | #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) | |
85 | #define RPC_INITCWND RPC_CWNDSCALE | |
86 | #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) | |
87 | ||
88 | #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) | |
1da177e4 | 89 | |
81c098af TT |
90 | /** |
91 | * xprt_register_transport - register a transport implementation | |
92 | * @transport: transport to register | |
93 | * | |
94 | * If a transport implementation is loaded as a kernel module, it can | |
95 | * call this interface to make itself known to the RPC client. | |
96 | * | |
97 | * Returns: | |
98 | * 0: transport successfully registered | |
99 | * -EEXIST: transport already registered | |
100 | * -EINVAL: transport module being unloaded | |
101 | */ | |
102 | int xprt_register_transport(struct xprt_class *transport) | |
103 | { | |
104 | struct xprt_class *t; | |
105 | int result; | |
106 | ||
107 | result = -EEXIST; | |
108 | spin_lock(&xprt_list_lock); | |
109 | list_for_each_entry(t, &xprt_list, list) { | |
110 | /* don't register the same transport class twice */ | |
4fa016eb | 111 | if (t->ident == transport->ident) |
81c098af TT |
112 | goto out; |
113 | } | |
114 | ||
c9f6cde6 DL |
115 | list_add_tail(&transport->list, &xprt_list); |
116 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
117 | transport->name); | |
118 | result = 0; | |
81c098af TT |
119 | |
120 | out: | |
121 | spin_unlock(&xprt_list_lock); | |
122 | return result; | |
123 | } | |
124 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
125 | ||
126 | /** | |
127 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 128 | * @transport: transport to unregister |
81c098af TT |
129 | * |
130 | * Returns: | |
131 | * 0: transport successfully unregistered | |
132 | * -ENOENT: transport never registered | |
133 | */ | |
134 | int xprt_unregister_transport(struct xprt_class *transport) | |
135 | { | |
136 | struct xprt_class *t; | |
137 | int result; | |
138 | ||
139 | result = 0; | |
140 | spin_lock(&xprt_list_lock); | |
141 | list_for_each_entry(t, &xprt_list, list) { | |
142 | if (t == transport) { | |
143 | printk(KERN_INFO | |
144 | "RPC: Unregistered %s transport module.\n", | |
145 | transport->name); | |
146 | list_del_init(&transport->list); | |
81c098af TT |
147 | goto out; |
148 | } | |
149 | } | |
150 | result = -ENOENT; | |
151 | ||
152 | out: | |
153 | spin_unlock(&xprt_list_lock); | |
154 | return result; | |
155 | } | |
156 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
157 | ||
441e3e24 TT |
158 | /** |
159 | * xprt_load_transport - load a transport implementation | |
160 | * @transport_name: transport to load | |
161 | * | |
162 | * Returns: | |
163 | * 0: transport successfully loaded | |
164 | * -ENOENT: transport module not available | |
165 | */ | |
166 | int xprt_load_transport(const char *transport_name) | |
167 | { | |
168 | struct xprt_class *t; | |
441e3e24 TT |
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); | |
ef7ffe8f | 180 | result = request_module("xprt%s", transport_name); |
441e3e24 TT |
181 | out: |
182 | return result; | |
183 | } | |
184 | EXPORT_SYMBOL_GPL(xprt_load_transport); | |
185 | ||
12a80469 CL |
186 | /** |
187 | * xprt_reserve_xprt - serialize write access to transports | |
188 | * @task: task that is requesting access to the transport | |
189 | * | |
190 | * This prevents mixing the payload of separate requests, and prevents | |
191 | * transport connects from colliding with writes. No congestion control | |
192 | * is provided. | |
193 | */ | |
194 | int xprt_reserve_xprt(struct rpc_task *task) | |
195 | { | |
12a80469 | 196 | struct rpc_rqst *req = task->tk_rqstp; |
343952fa | 197 | struct rpc_xprt *xprt = req->rq_xprt; |
12a80469 CL |
198 | |
199 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
200 | if (task == xprt->snd_task) | |
201 | return 1; | |
12a80469 CL |
202 | goto out_sleep; |
203 | } | |
204 | xprt->snd_task = task; | |
4d4a76f3 | 205 | req->rq_bytes_sent = 0; |
206 | req->rq_ntrans++; | |
207 | ||
12a80469 CL |
208 | return 1; |
209 | ||
210 | out_sleep: | |
46121cf7 | 211 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
212 | task->tk_pid, xprt); |
213 | task->tk_timeout = 0; | |
214 | task->tk_status = -EAGAIN; | |
ba3c578d | 215 | if (req->rq_ntrans) |
5d00837b | 216 | rpc_sleep_on(&xprt->resend, task, NULL); |
12a80469 | 217 | else |
5d00837b | 218 | rpc_sleep_on(&xprt->sending, task, NULL); |
12a80469 CL |
219 | return 0; |
220 | } | |
12444809 | 221 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 222 | |
632e3bdc TM |
223 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
224 | { | |
225 | xprt->snd_task = NULL; | |
226 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state) || xprt->shutdown) { | |
227 | smp_mb__before_clear_bit(); | |
228 | clear_bit(XPRT_LOCKED, &xprt->state); | |
229 | smp_mb__after_clear_bit(); | |
230 | } else | |
c1384c9c | 231 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
232 | } |
233 | ||
1da177e4 | 234 | /* |
12a80469 CL |
235 | * xprt_reserve_xprt_cong - serialize write access to transports |
236 | * @task: task that is requesting access to the transport | |
237 | * | |
238 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
239 | * integrated into the decision of whether a request is allowed to be | |
240 | * woken up and given access to the transport. | |
1da177e4 | 241 | */ |
12a80469 | 242 | int xprt_reserve_xprt_cong(struct rpc_task *task) |
1da177e4 | 243 | { |
12a80469 | 244 | struct rpc_xprt *xprt = task->tk_xprt; |
1da177e4 LT |
245 | struct rpc_rqst *req = task->tk_rqstp; |
246 | ||
2226feb6 | 247 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
248 | if (task == xprt->snd_task) |
249 | return 1; | |
1da177e4 LT |
250 | goto out_sleep; |
251 | } | |
12a80469 | 252 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
253 | xprt->snd_task = task; |
254 | if (req) { | |
255 | req->rq_bytes_sent = 0; | |
256 | req->rq_ntrans++; | |
257 | } | |
258 | return 1; | |
259 | } | |
632e3bdc | 260 | xprt_clear_locked(xprt); |
1da177e4 | 261 | out_sleep: |
46121cf7 | 262 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
263 | task->tk_timeout = 0; |
264 | task->tk_status = -EAGAIN; | |
265 | if (req && req->rq_ntrans) | |
5d00837b | 266 | rpc_sleep_on(&xprt->resend, task, NULL); |
1da177e4 | 267 | else |
5d00837b | 268 | rpc_sleep_on(&xprt->sending, task, NULL); |
1da177e4 LT |
269 | return 0; |
270 | } | |
12444809 | 271 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 272 | |
12a80469 | 273 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
274 | { |
275 | int retval; | |
276 | ||
4a0f8c04 | 277 | spin_lock_bh(&xprt->transport_lock); |
12a80469 | 278 | retval = xprt->ops->reserve_xprt(task); |
4a0f8c04 | 279 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
280 | return retval; |
281 | } | |
282 | ||
12a80469 | 283 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
49e9a890 CL |
284 | { |
285 | struct rpc_task *task; | |
286 | struct rpc_rqst *req; | |
287 | ||
288 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
289 | return; | |
290 | ||
291 | task = rpc_wake_up_next(&xprt->resend); | |
292 | if (!task) { | |
293 | task = rpc_wake_up_next(&xprt->sending); | |
294 | if (!task) | |
295 | goto out_unlock; | |
296 | } | |
297 | ||
298 | req = task->tk_rqstp; | |
299 | xprt->snd_task = task; | |
300 | if (req) { | |
301 | req->rq_bytes_sent = 0; | |
302 | req->rq_ntrans++; | |
303 | } | |
304 | return; | |
305 | ||
306 | out_unlock: | |
632e3bdc | 307 | xprt_clear_locked(xprt); |
49e9a890 CL |
308 | } |
309 | ||
310 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
1da177e4 LT |
311 | { |
312 | struct rpc_task *task; | |
313 | ||
2226feb6 | 314 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 315 | return; |
49e9a890 | 316 | if (RPCXPRT_CONGESTED(xprt)) |
1da177e4 LT |
317 | goto out_unlock; |
318 | task = rpc_wake_up_next(&xprt->resend); | |
319 | if (!task) { | |
320 | task = rpc_wake_up_next(&xprt->sending); | |
321 | if (!task) | |
322 | goto out_unlock; | |
323 | } | |
49e9a890 | 324 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 LT |
325 | struct rpc_rqst *req = task->tk_rqstp; |
326 | xprt->snd_task = task; | |
327 | if (req) { | |
328 | req->rq_bytes_sent = 0; | |
329 | req->rq_ntrans++; | |
330 | } | |
331 | return; | |
332 | } | |
333 | out_unlock: | |
632e3bdc | 334 | xprt_clear_locked(xprt); |
1da177e4 LT |
335 | } |
336 | ||
49e9a890 CL |
337 | /** |
338 | * xprt_release_xprt - allow other requests to use a transport | |
339 | * @xprt: transport with other tasks potentially waiting | |
340 | * @task: task that is releasing access to the transport | |
341 | * | |
342 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 343 | */ |
49e9a890 | 344 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
345 | { |
346 | if (xprt->snd_task == task) { | |
632e3bdc | 347 | xprt_clear_locked(xprt); |
1da177e4 LT |
348 | __xprt_lock_write_next(xprt); |
349 | } | |
350 | } | |
12444809 | 351 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 352 | |
49e9a890 CL |
353 | /** |
354 | * xprt_release_xprt_cong - allow other requests to use a transport | |
355 | * @xprt: transport with other tasks potentially waiting | |
356 | * @task: task that is releasing access to the transport | |
357 | * | |
358 | * Note that "task" can be NULL. Another task is awoken to use the | |
359 | * transport if the transport's congestion window allows it. | |
360 | */ | |
361 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
362 | { | |
363 | if (xprt->snd_task == task) { | |
632e3bdc | 364 | xprt_clear_locked(xprt); |
49e9a890 CL |
365 | __xprt_lock_write_next_cong(xprt); |
366 | } | |
367 | } | |
12444809 | 368 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
369 | |
370 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 371 | { |
4a0f8c04 | 372 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 373 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 374 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
375 | } |
376 | ||
1da177e4 LT |
377 | /* |
378 | * Van Jacobson congestion avoidance. Check if the congestion window | |
379 | * overflowed. Put the task to sleep if this is the case. | |
380 | */ | |
381 | static int | |
382 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
383 | { | |
384 | struct rpc_rqst *req = task->tk_rqstp; | |
385 | ||
386 | if (req->rq_cong) | |
387 | return 1; | |
46121cf7 | 388 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
389 | task->tk_pid, xprt->cong, xprt->cwnd); |
390 | if (RPCXPRT_CONGESTED(xprt)) | |
391 | return 0; | |
392 | req->rq_cong = 1; | |
393 | xprt->cong += RPC_CWNDSCALE; | |
394 | return 1; | |
395 | } | |
396 | ||
397 | /* | |
398 | * Adjust the congestion window, and wake up the next task | |
399 | * that has been sleeping due to congestion | |
400 | */ | |
401 | static void | |
402 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
403 | { | |
404 | if (!req->rq_cong) | |
405 | return; | |
406 | req->rq_cong = 0; | |
407 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 408 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
409 | } |
410 | ||
a58dd398 CL |
411 | /** |
412 | * xprt_release_rqst_cong - housekeeping when request is complete | |
413 | * @task: RPC request that recently completed | |
414 | * | |
415 | * Useful for transports that require congestion control. | |
416 | */ | |
417 | void xprt_release_rqst_cong(struct rpc_task *task) | |
418 | { | |
419 | __xprt_put_cong(task->tk_xprt, task->tk_rqstp); | |
420 | } | |
12444809 | 421 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 422 | |
46c0ee8b CL |
423 | /** |
424 | * xprt_adjust_cwnd - adjust transport congestion window | |
425 | * @task: recently completed RPC request used to adjust window | |
426 | * @result: result code of completed RPC request | |
427 | * | |
1da177e4 LT |
428 | * We use a time-smoothed congestion estimator to avoid heavy oscillation. |
429 | */ | |
46c0ee8b | 430 | void xprt_adjust_cwnd(struct rpc_task *task, int result) |
1da177e4 | 431 | { |
46c0ee8b CL |
432 | struct rpc_rqst *req = task->tk_rqstp; |
433 | struct rpc_xprt *xprt = task->tk_xprt; | |
434 | unsigned long cwnd = xprt->cwnd; | |
1da177e4 | 435 | |
1da177e4 LT |
436 | if (result >= 0 && cwnd <= xprt->cong) { |
437 | /* The (cwnd >> 1) term makes sure | |
438 | * the result gets rounded properly. */ | |
439 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
440 | if (cwnd > RPC_MAXCWND(xprt)) | |
441 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 442 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
443 | } else if (result == -ETIMEDOUT) { |
444 | cwnd >>= 1; | |
445 | if (cwnd < RPC_CWNDSCALE) | |
446 | cwnd = RPC_CWNDSCALE; | |
447 | } | |
46121cf7 | 448 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
449 | xprt->cong, xprt->cwnd, cwnd); |
450 | xprt->cwnd = cwnd; | |
46c0ee8b | 451 | __xprt_put_cong(xprt, req); |
1da177e4 | 452 | } |
12444809 | 453 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 454 | |
44fbac22 CL |
455 | /** |
456 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
457 | * @xprt: transport with waiting tasks | |
458 | * @status: result code to plant in each task before waking it | |
459 | * | |
460 | */ | |
461 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
462 | { | |
463 | if (status < 0) | |
464 | rpc_wake_up_status(&xprt->pending, status); | |
465 | else | |
466 | rpc_wake_up(&xprt->pending); | |
467 | } | |
12444809 | 468 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 469 | |
c7b2cae8 CL |
470 | /** |
471 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
472 | * @task: task to be put to sleep | |
0b80ae42 | 473 | * @action: function pointer to be executed after wait |
c7b2cae8 | 474 | */ |
b6ddf64f | 475 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
476 | { |
477 | struct rpc_rqst *req = task->tk_rqstp; | |
478 | struct rpc_xprt *xprt = req->rq_xprt; | |
479 | ||
480 | task->tk_timeout = req->rq_timeout; | |
b6ddf64f | 481 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 482 | } |
12444809 | 483 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
484 | |
485 | /** | |
486 | * xprt_write_space - wake the task waiting for transport output buffer space | |
487 | * @xprt: transport with waiting tasks | |
488 | * | |
489 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
490 | */ | |
491 | void xprt_write_space(struct rpc_xprt *xprt) | |
492 | { | |
493 | if (unlikely(xprt->shutdown)) | |
494 | return; | |
495 | ||
496 | spin_lock_bh(&xprt->transport_lock); | |
497 | if (xprt->snd_task) { | |
46121cf7 CL |
498 | dprintk("RPC: write space: waking waiting task on " |
499 | "xprt %p\n", xprt); | |
fda13939 | 500 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
501 | } |
502 | spin_unlock_bh(&xprt->transport_lock); | |
503 | } | |
12444809 | 504 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 505 | |
fe3aca29 CL |
506 | /** |
507 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
508 | * @task: task whose timeout is to be set | |
509 | * | |
510 | * Set a request's retransmit timeout based on the transport's | |
511 | * default timeout parameters. Used by transports that don't adjust | |
512 | * the retransmit timeout based on round-trip time estimation. | |
513 | */ | |
514 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
515 | { | |
516 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
517 | } | |
12444809 | 518 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 CL |
519 | |
520 | /* | |
521 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout | |
522 | * @task: task whose timeout is to be set | |
cca5172a | 523 | * |
fe3aca29 CL |
524 | * Set a request's retransmit timeout using the RTT estimator. |
525 | */ | |
526 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
527 | { | |
528 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
529 | struct rpc_clnt *clnt = task->tk_client; |
530 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 531 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 532 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
533 | |
534 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
535 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
536 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
537 | task->tk_timeout = max_timeout; | |
538 | } | |
12444809 | 539 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 540 | |
1da177e4 LT |
541 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
542 | { | |
ba7392bb | 543 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
544 | |
545 | req->rq_majortimeo = req->rq_timeout; | |
546 | if (to->to_exponential) | |
547 | req->rq_majortimeo <<= to->to_retries; | |
548 | else | |
549 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
550 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
551 | req->rq_majortimeo = to->to_maxval; | |
552 | req->rq_majortimeo += jiffies; | |
553 | } | |
554 | ||
9903cd1c CL |
555 | /** |
556 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
557 | * @req: RPC request containing parameters to use for the adjustment | |
558 | * | |
1da177e4 LT |
559 | */ |
560 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
561 | { | |
562 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 563 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
564 | int status = 0; |
565 | ||
566 | if (time_before(jiffies, req->rq_majortimeo)) { | |
567 | if (to->to_exponential) | |
568 | req->rq_timeout <<= 1; | |
569 | else | |
570 | req->rq_timeout += to->to_increment; | |
571 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
572 | req->rq_timeout = to->to_maxval; | |
573 | req->rq_retries++; | |
1da177e4 LT |
574 | } else { |
575 | req->rq_timeout = to->to_initval; | |
576 | req->rq_retries = 0; | |
577 | xprt_reset_majortimeo(req); | |
578 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 579 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 580 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 581 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
582 | status = -ETIMEDOUT; |
583 | } | |
584 | ||
585 | if (req->rq_timeout == 0) { | |
586 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
587 | req->rq_timeout = 5 * HZ; | |
588 | } | |
589 | return status; | |
590 | } | |
591 | ||
65f27f38 | 592 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 593 | { |
65f27f38 DH |
594 | struct rpc_xprt *xprt = |
595 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 596 | |
a246b010 | 597 | xprt->ops->close(xprt); |
66af1e55 | 598 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
1da177e4 LT |
599 | xprt_release_write(xprt, NULL); |
600 | } | |
601 | ||
9903cd1c | 602 | /** |
62da3b24 | 603 | * xprt_disconnect_done - mark a transport as disconnected |
9903cd1c CL |
604 | * @xprt: transport to flag for disconnect |
605 | * | |
1da177e4 | 606 | */ |
62da3b24 | 607 | void xprt_disconnect_done(struct rpc_xprt *xprt) |
1da177e4 | 608 | { |
46121cf7 | 609 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 610 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 611 | xprt_clear_connected(xprt); |
2a491991 | 612 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
4a0f8c04 | 613 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 614 | } |
62da3b24 | 615 | EXPORT_SYMBOL_GPL(xprt_disconnect_done); |
1da177e4 | 616 | |
66af1e55 TM |
617 | /** |
618 | * xprt_force_disconnect - force a transport to disconnect | |
619 | * @xprt: transport to disconnect | |
620 | * | |
621 | */ | |
622 | void xprt_force_disconnect(struct rpc_xprt *xprt) | |
623 | { | |
624 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
625 | spin_lock_bh(&xprt->transport_lock); | |
626 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
627 | /* Try to schedule an autoclose RPC call */ | |
628 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
629 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 630 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
66af1e55 TM |
631 | spin_unlock_bh(&xprt->transport_lock); |
632 | } | |
66af1e55 | 633 | |
7c1d71cf TM |
634 | /** |
635 | * xprt_conditional_disconnect - force a transport to disconnect | |
636 | * @xprt: transport to disconnect | |
637 | * @cookie: 'connection cookie' | |
638 | * | |
639 | * This attempts to break the connection if and only if 'cookie' matches | |
640 | * the current transport 'connection cookie'. It ensures that we don't | |
641 | * try to break the connection more than once when we need to retransmit | |
642 | * a batch of RPC requests. | |
643 | * | |
644 | */ | |
645 | void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) | |
646 | { | |
647 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
648 | spin_lock_bh(&xprt->transport_lock); | |
649 | if (cookie != xprt->connect_cookie) | |
650 | goto out; | |
651 | if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) | |
652 | goto out; | |
653 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
654 | /* Try to schedule an autoclose RPC call */ | |
655 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
656 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 657 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
7c1d71cf TM |
658 | out: |
659 | spin_unlock_bh(&xprt->transport_lock); | |
660 | } | |
661 | ||
1da177e4 LT |
662 | static void |
663 | xprt_init_autodisconnect(unsigned long data) | |
664 | { | |
665 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
666 | ||
4a0f8c04 | 667 | spin_lock(&xprt->transport_lock); |
1da177e4 LT |
668 | if (!list_empty(&xprt->recv) || xprt->shutdown) |
669 | goto out_abort; | |
2226feb6 | 670 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 671 | goto out_abort; |
4a0f8c04 | 672 | spin_unlock(&xprt->transport_lock); |
f75e6745 TM |
673 | set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); |
674 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
1da177e4 LT |
675 | return; |
676 | out_abort: | |
4a0f8c04 | 677 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
678 | } |
679 | ||
9903cd1c CL |
680 | /** |
681 | * xprt_connect - schedule a transport connect operation | |
682 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
683 | * |
684 | */ | |
685 | void xprt_connect(struct rpc_task *task) | |
686 | { | |
687 | struct rpc_xprt *xprt = task->tk_xprt; | |
688 | ||
46121cf7 | 689 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
690 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
691 | ||
ec739ef0 | 692 | if (!xprt_bound(xprt)) { |
01d37c42 | 693 | task->tk_status = -EAGAIN; |
1da177e4 LT |
694 | return; |
695 | } | |
696 | if (!xprt_lock_write(xprt, task)) | |
697 | return; | |
feb8ca37 TM |
698 | |
699 | if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) | |
700 | xprt->ops->close(xprt); | |
701 | ||
1da177e4 | 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 | |
a8ce4a8f | 708 | task->tk_timeout = task->tk_rqstp->rq_timeout; |
5d00837b | 709 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
0b9e7943 TM |
710 | |
711 | if (test_bit(XPRT_CLOSING, &xprt->state)) | |
712 | return; | |
713 | if (xprt_test_and_set_connecting(xprt)) | |
714 | return; | |
262ca07d | 715 | xprt->stat.connect_start = jiffies; |
a246b010 | 716 | xprt->ops->connect(task); |
1da177e4 | 717 | } |
1da177e4 LT |
718 | } |
719 | ||
9903cd1c | 720 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 LT |
721 | { |
722 | struct rpc_xprt *xprt = task->tk_xprt; | |
723 | ||
cd983ef8 | 724 | if (task->tk_status == 0) { |
262ca07d CL |
725 | xprt->stat.connect_count++; |
726 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 727 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
728 | task->tk_pid); |
729 | return; | |
730 | } | |
731 | ||
1da177e4 | 732 | switch (task->tk_status) { |
2a491991 TM |
733 | case -EAGAIN: |
734 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 735 | break; |
1da177e4 | 736 | case -ETIMEDOUT: |
46121cf7 CL |
737 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
738 | "out\n", task->tk_pid); | |
1da177e4 LT |
739 | break; |
740 | default: | |
46121cf7 CL |
741 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
742 | "server %s\n", task->tk_pid, -task->tk_status, | |
743 | task->tk_client->cl_server); | |
23475d66 CL |
744 | xprt_release_write(xprt, task); |
745 | task->tk_status = -EIO; | |
1da177e4 | 746 | } |
1da177e4 LT |
747 | } |
748 | ||
9903cd1c CL |
749 | /** |
750 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
751 | * @xprt: transport on which the original request was transmitted | |
752 | * @xid: RPC XID of incoming reply | |
753 | * | |
1da177e4 | 754 | */ |
d8ed029d | 755 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 | 756 | { |
8f3a6de3 | 757 | struct rpc_rqst *entry; |
1da177e4 | 758 | |
8f3a6de3 | 759 | list_for_each_entry(entry, &xprt->recv, rq_list) |
262ca07d CL |
760 | if (entry->rq_xid == xid) |
761 | return entry; | |
46121cf7 CL |
762 | |
763 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
764 | ntohl(xid)); | |
262ca07d CL |
765 | xprt->stat.bad_xids++; |
766 | return NULL; | |
1da177e4 | 767 | } |
12444809 | 768 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 769 | |
bbc72cea | 770 | static void xprt_update_rtt(struct rpc_task *task) |
1570c1e4 CL |
771 | { |
772 | struct rpc_rqst *req = task->tk_rqstp; | |
773 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
774 | unsigned timer = task->tk_msg.rpc_proc->p_timer; | |
d60dbb20 | 775 | long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); |
1570c1e4 CL |
776 | |
777 | if (timer) { | |
778 | if (req->rq_ntrans == 1) | |
ff839970 | 779 | rpc_update_rtt(rtt, timer, m); |
1570c1e4 CL |
780 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); |
781 | } | |
782 | } | |
783 | ||
9903cd1c CL |
784 | /** |
785 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 786 | * @task: RPC request that recently completed |
9903cd1c CL |
787 | * @copied: actual number of bytes received from the transport |
788 | * | |
1570c1e4 | 789 | * Caller holds transport lock. |
1da177e4 | 790 | */ |
1570c1e4 | 791 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 792 | { |
1570c1e4 | 793 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 794 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 795 | |
1570c1e4 CL |
796 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
797 | task->tk_pid, ntohl(req->rq_xid), copied); | |
1da177e4 | 798 | |
fda13939 | 799 | xprt->stat.recvs++; |
d60dbb20 | 800 | req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); |
bbc72cea CL |
801 | if (xprt->ops->timer != NULL) |
802 | xprt_update_rtt(task); | |
ef759a2e | 803 | |
1da177e4 | 804 | list_del_init(&req->rq_list); |
1e799b67 | 805 | req->rq_private_buf.len = copied; |
dd2b63d0 RL |
806 | /* Ensure all writes are done before we update */ |
807 | /* req->rq_reply_bytes_recvd */ | |
43ac3f29 | 808 | smp_wmb(); |
dd2b63d0 | 809 | req->rq_reply_bytes_recvd = copied; |
fda13939 | 810 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 811 | } |
12444809 | 812 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 813 | |
46c0ee8b | 814 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 815 | { |
46c0ee8b | 816 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
817 | struct rpc_xprt *xprt = req->rq_xprt; |
818 | ||
5d00837b TM |
819 | if (task->tk_status != -ETIMEDOUT) |
820 | return; | |
46121cf7 | 821 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 822 | |
5d00837b | 823 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 | 824 | if (!req->rq_reply_bytes_recvd) { |
46c0ee8b CL |
825 | if (xprt->ops->timer) |
826 | xprt->ops->timer(task); | |
5d00837b TM |
827 | } else |
828 | task->tk_status = 0; | |
829 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
830 | } |
831 | ||
4cfc7e60 RI |
832 | static inline int xprt_has_timer(struct rpc_xprt *xprt) |
833 | { | |
834 | return xprt->idle_timeout != 0; | |
835 | } | |
836 | ||
9903cd1c CL |
837 | /** |
838 | * xprt_prepare_transmit - reserve the transport before sending a request | |
839 | * @task: RPC task about to send a request | |
840 | * | |
1da177e4 | 841 | */ |
9903cd1c | 842 | int xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
843 | { |
844 | struct rpc_rqst *req = task->tk_rqstp; | |
845 | struct rpc_xprt *xprt = req->rq_xprt; | |
846 | int err = 0; | |
847 | ||
46121cf7 | 848 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 849 | |
4a0f8c04 | 850 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 RL |
851 | if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) { |
852 | err = req->rq_reply_bytes_recvd; | |
1da177e4 LT |
853 | goto out_unlock; |
854 | } | |
2a491991 | 855 | if (!xprt->ops->reserve_xprt(task)) |
1da177e4 | 856 | err = -EAGAIN; |
1da177e4 | 857 | out_unlock: |
4a0f8c04 | 858 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
859 | return err; |
860 | } | |
861 | ||
e0ab53de | 862 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 863 | { |
343952fa | 864 | xprt_release_write(task->tk_rqstp->rq_xprt, task); |
5e5ce5be TM |
865 | } |
866 | ||
9903cd1c CL |
867 | /** |
868 | * xprt_transmit - send an RPC request on a transport | |
869 | * @task: controlling RPC task | |
870 | * | |
871 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
872 | */ | |
873 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 874 | { |
1da177e4 LT |
875 | struct rpc_rqst *req = task->tk_rqstp; |
876 | struct rpc_xprt *xprt = req->rq_xprt; | |
a246b010 | 877 | int status; |
1da177e4 | 878 | |
46121cf7 | 879 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 880 | |
dd2b63d0 | 881 | if (!req->rq_reply_bytes_recvd) { |
55ae1aab RL |
882 | if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { |
883 | /* | |
884 | * Add to the list only if we're expecting a reply | |
885 | */ | |
4a0f8c04 | 886 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
887 | /* Update the softirq receive buffer */ |
888 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
889 | sizeof(req->rq_private_buf)); | |
890 | /* Add request to the receive list */ | |
891 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 892 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 893 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
894 | /* Turn off autodisconnect */ |
895 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
896 | } |
897 | } else if (!req->rq_bytes_sent) | |
898 | return; | |
899 | ||
7c1d71cf | 900 | req->rq_connect_cookie = xprt->connect_cookie; |
ff839970 | 901 | req->rq_xtime = ktime_get(); |
a246b010 | 902 | status = xprt->ops->send_request(task); |
c8485e4d TM |
903 | if (status != 0) { |
904 | task->tk_status = status; | |
905 | return; | |
906 | } | |
262ca07d | 907 | |
c8485e4d TM |
908 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
909 | spin_lock_bh(&xprt->transport_lock); | |
262ca07d | 910 | |
c8485e4d | 911 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 912 | |
c8485e4d TM |
913 | xprt->stat.sends++; |
914 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
915 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
1da177e4 | 916 | |
c8485e4d TM |
917 | /* Don't race with disconnect */ |
918 | if (!xprt_connected(xprt)) | |
919 | task->tk_status = -ENOTCONN; | |
dd2b63d0 | 920 | else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) { |
55ae1aab RL |
921 | /* |
922 | * Sleep on the pending queue since | |
923 | * we're expecting a reply. | |
924 | */ | |
c8485e4d | 925 | rpc_sleep_on(&xprt->pending, task, xprt_timer); |
55ae1aab | 926 | } |
c8485e4d | 927 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
928 | } |
929 | ||
ee5ebe85 | 930 | static void xprt_alloc_slot(struct rpc_task *task) |
1da177e4 LT |
931 | { |
932 | struct rpc_xprt *xprt = task->tk_xprt; | |
933 | ||
934 | task->tk_status = 0; | |
935 | if (task->tk_rqstp) | |
936 | return; | |
937 | if (!list_empty(&xprt->free)) { | |
938 | struct rpc_rqst *req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); | |
939 | list_del_init(&req->rq_list); | |
940 | task->tk_rqstp = req; | |
941 | xprt_request_init(task, xprt); | |
942 | return; | |
943 | } | |
46121cf7 | 944 | dprintk("RPC: waiting for request slot\n"); |
1da177e4 LT |
945 | task->tk_status = -EAGAIN; |
946 | task->tk_timeout = 0; | |
5d00837b | 947 | rpc_sleep_on(&xprt->backlog, task, NULL); |
1da177e4 LT |
948 | } |
949 | ||
ee5ebe85 TM |
950 | static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) |
951 | { | |
952 | memset(req, 0, sizeof(*req)); /* mark unused */ | |
953 | ||
954 | spin_lock(&xprt->reserve_lock); | |
955 | list_add(&req->rq_list, &xprt->free); | |
956 | rpc_wake_up_next(&xprt->backlog); | |
957 | spin_unlock(&xprt->reserve_lock); | |
958 | } | |
959 | ||
37aa2133 | 960 | struct rpc_xprt *xprt_alloc(struct net *net, int size, int max_req) |
bd1722d4 PE |
961 | { |
962 | struct rpc_xprt *xprt; | |
963 | ||
964 | xprt = kzalloc(size, GFP_KERNEL); | |
965 | if (xprt == NULL) | |
966 | goto out; | |
a8de240a | 967 | atomic_set(&xprt->count, 1); |
bd1722d4 PE |
968 | |
969 | xprt->max_reqs = max_req; | |
970 | xprt->slot = kcalloc(max_req, sizeof(struct rpc_rqst), GFP_KERNEL); | |
971 | if (xprt->slot == NULL) | |
972 | goto out_free; | |
973 | ||
37aa2133 | 974 | xprt->xprt_net = get_net(net); |
bd1722d4 PE |
975 | return xprt; |
976 | ||
977 | out_free: | |
978 | kfree(xprt); | |
979 | out: | |
980 | return NULL; | |
981 | } | |
982 | EXPORT_SYMBOL_GPL(xprt_alloc); | |
983 | ||
e204e621 PE |
984 | void xprt_free(struct rpc_xprt *xprt) |
985 | { | |
37aa2133 | 986 | put_net(xprt->xprt_net); |
e204e621 PE |
987 | kfree(xprt->slot); |
988 | kfree(xprt); | |
989 | } | |
990 | EXPORT_SYMBOL_GPL(xprt_free); | |
991 | ||
9903cd1c CL |
992 | /** |
993 | * xprt_reserve - allocate an RPC request slot | |
994 | * @task: RPC task requesting a slot allocation | |
995 | * | |
996 | * If no more slots are available, place the task on the transport's | |
997 | * backlog queue. | |
998 | */ | |
999 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 LT |
1000 | { |
1001 | struct rpc_xprt *xprt = task->tk_xprt; | |
1002 | ||
1003 | task->tk_status = -EIO; | |
0065db32 | 1004 | spin_lock(&xprt->reserve_lock); |
ee5ebe85 | 1005 | xprt_alloc_slot(task); |
0065db32 | 1006 | spin_unlock(&xprt->reserve_lock); |
1da177e4 LT |
1007 | } |
1008 | ||
d8ed029d | 1009 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 | 1010 | { |
0eae88f3 | 1011 | return (__force __be32)xprt->xid++; |
1da177e4 LT |
1012 | } |
1013 | ||
1014 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
1015 | { | |
bf3fcf89 | 1016 | xprt->xid = net_random(); |
1da177e4 LT |
1017 | } |
1018 | ||
9903cd1c | 1019 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
1020 | { |
1021 | struct rpc_rqst *req = task->tk_rqstp; | |
1022 | ||
ba7392bb | 1023 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
1024 | req->rq_task = task; |
1025 | req->rq_xprt = xprt; | |
02107148 | 1026 | req->rq_buffer = NULL; |
1da177e4 | 1027 | req->rq_xid = xprt_alloc_xid(xprt); |
ead5e1c2 | 1028 | req->rq_release_snd_buf = NULL; |
da45828e | 1029 | xprt_reset_majortimeo(req); |
46121cf7 | 1030 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
1031 | req, ntohl(req->rq_xid)); |
1032 | } | |
1033 | ||
9903cd1c CL |
1034 | /** |
1035 | * xprt_release - release an RPC request slot | |
1036 | * @task: task which is finished with the slot | |
1037 | * | |
1da177e4 | 1038 | */ |
9903cd1c | 1039 | void xprt_release(struct rpc_task *task) |
1da177e4 | 1040 | { |
55ae1aab | 1041 | struct rpc_xprt *xprt; |
1da177e4 LT |
1042 | struct rpc_rqst *req; |
1043 | ||
1044 | if (!(req = task->tk_rqstp)) | |
1045 | return; | |
55ae1aab | 1046 | |
55ae1aab | 1047 | xprt = req->rq_xprt; |
11c556b3 | 1048 | rpc_count_iostats(task); |
4a0f8c04 | 1049 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 1050 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
1051 | if (xprt->ops->release_request) |
1052 | xprt->ops->release_request(task); | |
1da177e4 LT |
1053 | if (!list_empty(&req->rq_list)) |
1054 | list_del(&req->rq_list); | |
1055 | xprt->last_used = jiffies; | |
4cfc7e60 | 1056 | if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) |
a246b010 | 1057 | mod_timer(&xprt->timer, |
03bf4b70 | 1058 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1059 | spin_unlock_bh(&xprt->transport_lock); |
ee5ebe85 | 1060 | if (req->rq_buffer) |
55ae1aab | 1061 | xprt->ops->buf_free(req->rq_buffer); |
a17c2153 TM |
1062 | if (req->rq_cred != NULL) |
1063 | put_rpccred(req->rq_cred); | |
1da177e4 | 1064 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1065 | if (req->rq_release_snd_buf) |
1066 | req->rq_release_snd_buf(req); | |
55ae1aab | 1067 | |
46121cf7 | 1068 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
ee5ebe85 TM |
1069 | if (likely(!bc_prealloc(req))) |
1070 | xprt_free_slot(xprt, req); | |
1071 | else | |
c9acb42e | 1072 | xprt_free_bc_request(req); |
1da177e4 LT |
1073 | } |
1074 | ||
c2866763 CL |
1075 | /** |
1076 | * xprt_create_transport - create an RPC transport | |
96802a09 | 1077 | * @args: rpc transport creation arguments |
c2866763 CL |
1078 | * |
1079 | */ | |
3c341b0b | 1080 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) |
c2866763 | 1081 | { |
c2866763 CL |
1082 | struct rpc_xprt *xprt; |
1083 | struct rpc_rqst *req; | |
bc25571e | 1084 | struct xprt_class *t; |
c2866763 | 1085 | |
bc25571e TT |
1086 | spin_lock(&xprt_list_lock); |
1087 | list_for_each_entry(t, &xprt_list, list) { | |
4fa016eb | 1088 | if (t->ident == args->ident) { |
bc25571e TT |
1089 | spin_unlock(&xprt_list_lock); |
1090 | goto found; | |
1091 | } | |
c2866763 | 1092 | } |
bc25571e | 1093 | spin_unlock(&xprt_list_lock); |
4fa016eb | 1094 | printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); |
bc25571e TT |
1095 | return ERR_PTR(-EIO); |
1096 | ||
1097 | found: | |
1098 | xprt = t->setup(args); | |
c8541ecd | 1099 | if (IS_ERR(xprt)) { |
46121cf7 | 1100 | dprintk("RPC: xprt_create_transport: failed, %ld\n", |
c8541ecd CL |
1101 | -PTR_ERR(xprt)); |
1102 | return xprt; | |
c2866763 | 1103 | } |
f0418aa4 BF |
1104 | if (test_and_set_bit(XPRT_INITIALIZED, &xprt->state)) |
1105 | /* ->setup returned a pre-initialized xprt: */ | |
1106 | return xprt; | |
c2866763 CL |
1107 | |
1108 | spin_lock_init(&xprt->transport_lock); | |
1109 | spin_lock_init(&xprt->reserve_lock); | |
1110 | ||
1111 | INIT_LIST_HEAD(&xprt->free); | |
1112 | INIT_LIST_HEAD(&xprt->recv); | |
f9acac1a RL |
1113 | #if defined(CONFIG_NFS_V4_1) |
1114 | spin_lock_init(&xprt->bc_pa_lock); | |
1115 | INIT_LIST_HEAD(&xprt->bc_pa_list); | |
1116 | #endif /* CONFIG_NFS_V4_1 */ | |
1117 | ||
65f27f38 | 1118 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
4cfc7e60 RI |
1119 | if (xprt_has_timer(xprt)) |
1120 | setup_timer(&xprt->timer, xprt_init_autodisconnect, | |
1121 | (unsigned long)xprt); | |
1122 | else | |
1123 | init_timer(&xprt->timer); | |
c2866763 CL |
1124 | xprt->last_used = jiffies; |
1125 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1126 | xprt->bind_index = 0; |
c2866763 CL |
1127 | |
1128 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1129 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
1130 | rpc_init_wait_queue(&xprt->sending, "xprt_sending"); | |
1131 | rpc_init_wait_queue(&xprt->resend, "xprt_resend"); | |
1132 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); | |
1133 | ||
1134 | /* initialize free list */ | |
1135 | for (req = &xprt->slot[xprt->max_reqs-1]; req >= &xprt->slot[0]; req--) | |
1136 | list_add(&req->rq_list, &xprt->free); | |
1137 | ||
1138 | xprt_init_xid(xprt); | |
1139 | ||
46121cf7 | 1140 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 | 1141 | xprt->max_reqs); |
c2866763 CL |
1142 | return xprt; |
1143 | } | |
1144 | ||
9903cd1c CL |
1145 | /** |
1146 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
a8de240a | 1147 | * @xprt: transport to destroy |
9903cd1c | 1148 | * |
1da177e4 | 1149 | */ |
a8de240a | 1150 | static void xprt_destroy(struct rpc_xprt *xprt) |
1da177e4 | 1151 | { |
46121cf7 | 1152 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 TM |
1153 | xprt->shutdown = 1; |
1154 | del_timer_sync(&xprt->timer); | |
c8541ecd | 1155 | |
f6a1cc89 TM |
1156 | rpc_destroy_wait_queue(&xprt->binding); |
1157 | rpc_destroy_wait_queue(&xprt->pending); | |
1158 | rpc_destroy_wait_queue(&xprt->sending); | |
1159 | rpc_destroy_wait_queue(&xprt->resend); | |
1160 | rpc_destroy_wait_queue(&xprt->backlog); | |
c3ae62ae | 1161 | cancel_work_sync(&xprt->task_cleanup); |
c8541ecd CL |
1162 | /* |
1163 | * Tear down transport state and free the rpc_xprt | |
1164 | */ | |
a246b010 | 1165 | xprt->ops->destroy(xprt); |
6b6ca86b | 1166 | } |
1da177e4 | 1167 | |
6b6ca86b TM |
1168 | /** |
1169 | * xprt_put - release a reference to an RPC transport. | |
1170 | * @xprt: pointer to the transport | |
1171 | * | |
1172 | */ | |
1173 | void xprt_put(struct rpc_xprt *xprt) | |
1174 | { | |
a8de240a TM |
1175 | if (atomic_dec_and_test(&xprt->count)) |
1176 | xprt_destroy(xprt); | |
6b6ca86b TM |
1177 | } |
1178 | ||
1179 | /** | |
1180 | * xprt_get - return a reference to an RPC transport. | |
1181 | * @xprt: pointer to the transport | |
1182 | * | |
1183 | */ | |
1184 | struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) | |
1185 | { | |
a8de240a TM |
1186 | if (atomic_inc_not_zero(&xprt->count)) |
1187 | return xprt; | |
1188 | return NULL; | |
1da177e4 | 1189 | } |