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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 | */ | |
21de0a95 | 65 | static void xprt_init(struct rpc_xprt *xprt, struct net *net); |
1da177e4 | 66 | static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); |
1da177e4 | 67 | static void xprt_connect_status(struct rpc_task *task); |
1da177e4 | 68 | static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
4e0038b6 | 69 | static void xprt_destroy(struct rpc_xprt *xprt); |
1da177e4 | 70 | |
5ba03e82 | 71 | static DEFINE_SPINLOCK(xprt_list_lock); |
81c098af TT |
72 | static LIST_HEAD(xprt_list); |
73 | ||
555ee3af CL |
74 | /* |
75 | * The transport code maintains an estimate on the maximum number of out- | |
76 | * standing RPC requests, using a smoothed version of the congestion | |
77 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
78 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
79 | * halved; otherwise, it is incremented by 1/cwnd when | |
80 | * | |
81 | * - a reply is received and | |
82 | * - a full number of requests are outstanding and | |
83 | * - the congestion window hasn't been updated recently. | |
84 | */ | |
85 | #define RPC_CWNDSHIFT (8U) | |
86 | #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) | |
87 | #define RPC_INITCWND RPC_CWNDSCALE | |
88 | #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) | |
89 | ||
90 | #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) | |
1da177e4 | 91 | |
81c098af TT |
92 | /** |
93 | * xprt_register_transport - register a transport implementation | |
94 | * @transport: transport to register | |
95 | * | |
96 | * If a transport implementation is loaded as a kernel module, it can | |
97 | * call this interface to make itself known to the RPC client. | |
98 | * | |
99 | * Returns: | |
100 | * 0: transport successfully registered | |
101 | * -EEXIST: transport already registered | |
102 | * -EINVAL: transport module being unloaded | |
103 | */ | |
104 | int xprt_register_transport(struct xprt_class *transport) | |
105 | { | |
106 | struct xprt_class *t; | |
107 | int result; | |
108 | ||
109 | result = -EEXIST; | |
110 | spin_lock(&xprt_list_lock); | |
111 | list_for_each_entry(t, &xprt_list, list) { | |
112 | /* don't register the same transport class twice */ | |
4fa016eb | 113 | if (t->ident == transport->ident) |
81c098af TT |
114 | goto out; |
115 | } | |
116 | ||
c9f6cde6 DL |
117 | list_add_tail(&transport->list, &xprt_list); |
118 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
119 | transport->name); | |
120 | result = 0; | |
81c098af TT |
121 | |
122 | out: | |
123 | spin_unlock(&xprt_list_lock); | |
124 | return result; | |
125 | } | |
126 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
127 | ||
128 | /** | |
129 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 130 | * @transport: transport to unregister |
81c098af TT |
131 | * |
132 | * Returns: | |
133 | * 0: transport successfully unregistered | |
134 | * -ENOENT: transport never registered | |
135 | */ | |
136 | int xprt_unregister_transport(struct xprt_class *transport) | |
137 | { | |
138 | struct xprt_class *t; | |
139 | int result; | |
140 | ||
141 | result = 0; | |
142 | spin_lock(&xprt_list_lock); | |
143 | list_for_each_entry(t, &xprt_list, list) { | |
144 | if (t == transport) { | |
145 | printk(KERN_INFO | |
146 | "RPC: Unregistered %s transport module.\n", | |
147 | transport->name); | |
148 | list_del_init(&transport->list); | |
81c098af TT |
149 | goto out; |
150 | } | |
151 | } | |
152 | result = -ENOENT; | |
153 | ||
154 | out: | |
155 | spin_unlock(&xprt_list_lock); | |
156 | return result; | |
157 | } | |
158 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
159 | ||
441e3e24 TT |
160 | /** |
161 | * xprt_load_transport - load a transport implementation | |
162 | * @transport_name: transport to load | |
163 | * | |
164 | * Returns: | |
165 | * 0: transport successfully loaded | |
166 | * -ENOENT: transport module not available | |
167 | */ | |
168 | int xprt_load_transport(const char *transport_name) | |
169 | { | |
170 | struct xprt_class *t; | |
441e3e24 TT |
171 | int result; |
172 | ||
173 | result = 0; | |
174 | spin_lock(&xprt_list_lock); | |
175 | list_for_each_entry(t, &xprt_list, list) { | |
176 | if (strcmp(t->name, transport_name) == 0) { | |
177 | spin_unlock(&xprt_list_lock); | |
178 | goto out; | |
179 | } | |
180 | } | |
181 | spin_unlock(&xprt_list_lock); | |
ef7ffe8f | 182 | result = request_module("xprt%s", transport_name); |
441e3e24 TT |
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 | |
177c27bf | 191 | * @xprt: pointer to the target transport |
12a80469 CL |
192 | * |
193 | * This prevents mixing the payload of separate requests, and prevents | |
194 | * transport connects from colliding with writes. No congestion control | |
195 | * is provided. | |
196 | */ | |
43cedbf0 | 197 | int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
12a80469 | 198 | { |
12a80469 | 199 | struct rpc_rqst *req = task->tk_rqstp; |
34006cee | 200 | int priority; |
12a80469 CL |
201 | |
202 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
203 | if (task == xprt->snd_task) | |
204 | return 1; | |
12a80469 CL |
205 | goto out_sleep; |
206 | } | |
207 | xprt->snd_task = task; | |
92551948 | 208 | if (req != NULL) |
43cedbf0 | 209 | req->rq_ntrans++; |
4d4a76f3 | 210 | |
12a80469 CL |
211 | return 1; |
212 | ||
213 | out_sleep: | |
46121cf7 | 214 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
215 | task->tk_pid, xprt); |
216 | task->tk_timeout = 0; | |
217 | task->tk_status = -EAGAIN; | |
34006cee TM |
218 | if (req == NULL) |
219 | priority = RPC_PRIORITY_LOW; | |
220 | else if (!req->rq_ntrans) | |
221 | priority = RPC_PRIORITY_NORMAL; | |
12a80469 | 222 | else |
34006cee TM |
223 | priority = RPC_PRIORITY_HIGH; |
224 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
12a80469 CL |
225 | return 0; |
226 | } | |
12444809 | 227 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 228 | |
632e3bdc TM |
229 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
230 | { | |
231 | xprt->snd_task = NULL; | |
d19751e7 | 232 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { |
4e857c58 | 233 | smp_mb__before_atomic(); |
632e3bdc | 234 | clear_bit(XPRT_LOCKED, &xprt->state); |
4e857c58 | 235 | smp_mb__after_atomic(); |
632e3bdc | 236 | } else |
c1384c9c | 237 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
238 | } |
239 | ||
1da177e4 | 240 | /* |
12a80469 CL |
241 | * xprt_reserve_xprt_cong - serialize write access to transports |
242 | * @task: task that is requesting access to the transport | |
243 | * | |
244 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
245 | * integrated into the decision of whether a request is allowed to be | |
246 | * woken up and given access to the transport. | |
1da177e4 | 247 | */ |
43cedbf0 | 248 | int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
249 | { |
250 | struct rpc_rqst *req = task->tk_rqstp; | |
34006cee | 251 | int priority; |
1da177e4 | 252 | |
2226feb6 | 253 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
254 | if (task == xprt->snd_task) |
255 | return 1; | |
1da177e4 LT |
256 | goto out_sleep; |
257 | } | |
43cedbf0 TM |
258 | if (req == NULL) { |
259 | xprt->snd_task = task; | |
260 | return 1; | |
261 | } | |
12a80469 | 262 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 263 | xprt->snd_task = task; |
43cedbf0 | 264 | req->rq_ntrans++; |
1da177e4 LT |
265 | return 1; |
266 | } | |
632e3bdc | 267 | xprt_clear_locked(xprt); |
1da177e4 | 268 | out_sleep: |
46121cf7 | 269 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
270 | task->tk_timeout = 0; |
271 | task->tk_status = -EAGAIN; | |
34006cee TM |
272 | if (req == NULL) |
273 | priority = RPC_PRIORITY_LOW; | |
274 | else if (!req->rq_ntrans) | |
275 | priority = RPC_PRIORITY_NORMAL; | |
1da177e4 | 276 | else |
34006cee TM |
277 | priority = RPC_PRIORITY_HIGH; |
278 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
1da177e4 LT |
279 | return 0; |
280 | } | |
12444809 | 281 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 282 | |
12a80469 | 283 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
284 | { |
285 | int retval; | |
286 | ||
4a0f8c04 | 287 | spin_lock_bh(&xprt->transport_lock); |
43cedbf0 | 288 | retval = xprt->ops->reserve_xprt(xprt, task); |
4a0f8c04 | 289 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
290 | return retval; |
291 | } | |
292 | ||
961a828d | 293 | static bool __xprt_lock_write_func(struct rpc_task *task, void *data) |
49e9a890 | 294 | { |
961a828d | 295 | struct rpc_xprt *xprt = data; |
49e9a890 CL |
296 | struct rpc_rqst *req; |
297 | ||
49e9a890 CL |
298 | req = task->tk_rqstp; |
299 | xprt->snd_task = task; | |
92551948 | 300 | if (req) |
49e9a890 | 301 | req->rq_ntrans++; |
961a828d TM |
302 | return true; |
303 | } | |
49e9a890 | 304 | |
961a828d TM |
305 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
306 | { | |
307 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
308 | return; | |
309 | ||
310 | if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt)) | |
311 | return; | |
632e3bdc | 312 | xprt_clear_locked(xprt); |
49e9a890 CL |
313 | } |
314 | ||
961a828d | 315 | static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) |
1da177e4 | 316 | { |
961a828d | 317 | struct rpc_xprt *xprt = data; |
43cedbf0 | 318 | struct rpc_rqst *req; |
1da177e4 | 319 | |
43cedbf0 TM |
320 | req = task->tk_rqstp; |
321 | if (req == NULL) { | |
322 | xprt->snd_task = task; | |
961a828d | 323 | return true; |
43cedbf0 | 324 | } |
49e9a890 | 325 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 326 | xprt->snd_task = task; |
43cedbf0 | 327 | req->rq_ntrans++; |
961a828d | 328 | return true; |
1da177e4 | 329 | } |
961a828d TM |
330 | return false; |
331 | } | |
332 | ||
333 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
334 | { | |
335 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
336 | return; | |
337 | if (RPCXPRT_CONGESTED(xprt)) | |
338 | goto out_unlock; | |
339 | if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt)) | |
340 | return; | |
1da177e4 | 341 | out_unlock: |
632e3bdc | 342 | xprt_clear_locked(xprt); |
1da177e4 LT |
343 | } |
344 | ||
49e9a890 CL |
345 | /** |
346 | * xprt_release_xprt - allow other requests to use a transport | |
347 | * @xprt: transport with other tasks potentially waiting | |
348 | * @task: task that is releasing access to the transport | |
349 | * | |
350 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 351 | */ |
49e9a890 | 352 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
353 | { |
354 | if (xprt->snd_task == task) { | |
ee071eff TM |
355 | if (task != NULL) { |
356 | struct rpc_rqst *req = task->tk_rqstp; | |
357 | if (req != NULL) | |
358 | req->rq_bytes_sent = 0; | |
359 | } | |
632e3bdc | 360 | xprt_clear_locked(xprt); |
1da177e4 LT |
361 | __xprt_lock_write_next(xprt); |
362 | } | |
363 | } | |
12444809 | 364 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 365 | |
49e9a890 CL |
366 | /** |
367 | * xprt_release_xprt_cong - allow other requests to use a transport | |
368 | * @xprt: transport with other tasks potentially waiting | |
369 | * @task: task that is releasing access to the transport | |
370 | * | |
371 | * Note that "task" can be NULL. Another task is awoken to use the | |
372 | * transport if the transport's congestion window allows it. | |
373 | */ | |
374 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
375 | { | |
376 | if (xprt->snd_task == task) { | |
ee071eff TM |
377 | if (task != NULL) { |
378 | struct rpc_rqst *req = task->tk_rqstp; | |
379 | if (req != NULL) | |
380 | req->rq_bytes_sent = 0; | |
381 | } | |
632e3bdc | 382 | xprt_clear_locked(xprt); |
49e9a890 CL |
383 | __xprt_lock_write_next_cong(xprt); |
384 | } | |
385 | } | |
12444809 | 386 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
387 | |
388 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 389 | { |
4a0f8c04 | 390 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 391 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 392 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
393 | } |
394 | ||
1da177e4 LT |
395 | /* |
396 | * Van Jacobson congestion avoidance. Check if the congestion window | |
397 | * overflowed. Put the task to sleep if this is the case. | |
398 | */ | |
399 | static int | |
400 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
401 | { | |
402 | struct rpc_rqst *req = task->tk_rqstp; | |
403 | ||
404 | if (req->rq_cong) | |
405 | return 1; | |
46121cf7 | 406 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
407 | task->tk_pid, xprt->cong, xprt->cwnd); |
408 | if (RPCXPRT_CONGESTED(xprt)) | |
409 | return 0; | |
410 | req->rq_cong = 1; | |
411 | xprt->cong += RPC_CWNDSCALE; | |
412 | return 1; | |
413 | } | |
414 | ||
415 | /* | |
416 | * Adjust the congestion window, and wake up the next task | |
417 | * that has been sleeping due to congestion | |
418 | */ | |
419 | static void | |
420 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
421 | { | |
422 | if (!req->rq_cong) | |
423 | return; | |
424 | req->rq_cong = 0; | |
425 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 426 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
427 | } |
428 | ||
a58dd398 CL |
429 | /** |
430 | * xprt_release_rqst_cong - housekeeping when request is complete | |
431 | * @task: RPC request that recently completed | |
432 | * | |
433 | * Useful for transports that require congestion control. | |
434 | */ | |
435 | void xprt_release_rqst_cong(struct rpc_task *task) | |
436 | { | |
a4f0835c TM |
437 | struct rpc_rqst *req = task->tk_rqstp; |
438 | ||
439 | __xprt_put_cong(req->rq_xprt, req); | |
a58dd398 | 440 | } |
12444809 | 441 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 442 | |
46c0ee8b CL |
443 | /** |
444 | * xprt_adjust_cwnd - adjust transport congestion window | |
6a24dfb6 | 445 | * @xprt: pointer to xprt |
46c0ee8b CL |
446 | * @task: recently completed RPC request used to adjust window |
447 | * @result: result code of completed RPC request | |
448 | * | |
1da177e4 LT |
449 | * We use a time-smoothed congestion estimator to avoid heavy oscillation. |
450 | */ | |
6a24dfb6 | 451 | void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) |
1da177e4 | 452 | { |
46c0ee8b | 453 | struct rpc_rqst *req = task->tk_rqstp; |
46c0ee8b | 454 | unsigned long cwnd = xprt->cwnd; |
1da177e4 | 455 | |
1da177e4 LT |
456 | if (result >= 0 && cwnd <= xprt->cong) { |
457 | /* The (cwnd >> 1) term makes sure | |
458 | * the result gets rounded properly. */ | |
459 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
460 | if (cwnd > RPC_MAXCWND(xprt)) | |
461 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 462 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
463 | } else if (result == -ETIMEDOUT) { |
464 | cwnd >>= 1; | |
465 | if (cwnd < RPC_CWNDSCALE) | |
466 | cwnd = RPC_CWNDSCALE; | |
467 | } | |
46121cf7 | 468 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
469 | xprt->cong, xprt->cwnd, cwnd); |
470 | xprt->cwnd = cwnd; | |
46c0ee8b | 471 | __xprt_put_cong(xprt, req); |
1da177e4 | 472 | } |
12444809 | 473 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 474 | |
44fbac22 CL |
475 | /** |
476 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
477 | * @xprt: transport with waiting tasks | |
478 | * @status: result code to plant in each task before waking it | |
479 | * | |
480 | */ | |
481 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
482 | { | |
483 | if (status < 0) | |
484 | rpc_wake_up_status(&xprt->pending, status); | |
485 | else | |
486 | rpc_wake_up(&xprt->pending); | |
487 | } | |
12444809 | 488 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 489 | |
c7b2cae8 CL |
490 | /** |
491 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
492 | * @task: task to be put to sleep | |
0b80ae42 | 493 | * @action: function pointer to be executed after wait |
a9a6b52e TM |
494 | * |
495 | * Note that we only set the timer for the case of RPC_IS_SOFT(), since | |
496 | * we don't in general want to force a socket disconnection due to | |
497 | * an incomplete RPC call transmission. | |
c7b2cae8 | 498 | */ |
b6ddf64f | 499 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
500 | { |
501 | struct rpc_rqst *req = task->tk_rqstp; | |
502 | struct rpc_xprt *xprt = req->rq_xprt; | |
503 | ||
a9a6b52e | 504 | task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; |
b6ddf64f | 505 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 506 | } |
12444809 | 507 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
508 | |
509 | /** | |
510 | * xprt_write_space - wake the task waiting for transport output buffer space | |
511 | * @xprt: transport with waiting tasks | |
512 | * | |
513 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
514 | */ | |
515 | void xprt_write_space(struct rpc_xprt *xprt) | |
516 | { | |
c7b2cae8 CL |
517 | spin_lock_bh(&xprt->transport_lock); |
518 | if (xprt->snd_task) { | |
46121cf7 CL |
519 | dprintk("RPC: write space: waking waiting task on " |
520 | "xprt %p\n", xprt); | |
fda13939 | 521 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
522 | } |
523 | spin_unlock_bh(&xprt->transport_lock); | |
524 | } | |
12444809 | 525 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 526 | |
fe3aca29 CL |
527 | /** |
528 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
529 | * @task: task whose timeout is to be set | |
530 | * | |
531 | * Set a request's retransmit timeout based on the transport's | |
532 | * default timeout parameters. Used by transports that don't adjust | |
533 | * the retransmit timeout based on round-trip time estimation. | |
534 | */ | |
535 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
536 | { | |
537 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
538 | } | |
12444809 | 539 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 | 540 | |
2c53040f | 541 | /** |
fe3aca29 CL |
542 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout |
543 | * @task: task whose timeout is to be set | |
cca5172a | 544 | * |
fe3aca29 CL |
545 | * Set a request's retransmit timeout using the RTT estimator. |
546 | */ | |
547 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
548 | { | |
549 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
550 | struct rpc_clnt *clnt = task->tk_client; |
551 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 552 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 553 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
554 | |
555 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
556 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
557 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
558 | task->tk_timeout = max_timeout; | |
559 | } | |
12444809 | 560 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 561 | |
1da177e4 LT |
562 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
563 | { | |
ba7392bb | 564 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
565 | |
566 | req->rq_majortimeo = req->rq_timeout; | |
567 | if (to->to_exponential) | |
568 | req->rq_majortimeo <<= to->to_retries; | |
569 | else | |
570 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
571 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
572 | req->rq_majortimeo = to->to_maxval; | |
573 | req->rq_majortimeo += jiffies; | |
574 | } | |
575 | ||
9903cd1c CL |
576 | /** |
577 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
578 | * @req: RPC request containing parameters to use for the adjustment | |
579 | * | |
1da177e4 LT |
580 | */ |
581 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
582 | { | |
583 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 584 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
585 | int status = 0; |
586 | ||
587 | if (time_before(jiffies, req->rq_majortimeo)) { | |
588 | if (to->to_exponential) | |
589 | req->rq_timeout <<= 1; | |
590 | else | |
591 | req->rq_timeout += to->to_increment; | |
592 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
593 | req->rq_timeout = to->to_maxval; | |
594 | req->rq_retries++; | |
1da177e4 LT |
595 | } else { |
596 | req->rq_timeout = to->to_initval; | |
597 | req->rq_retries = 0; | |
598 | xprt_reset_majortimeo(req); | |
599 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 600 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 601 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 602 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
603 | status = -ETIMEDOUT; |
604 | } | |
605 | ||
606 | if (req->rq_timeout == 0) { | |
607 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
608 | req->rq_timeout = 5 * HZ; | |
609 | } | |
610 | return status; | |
611 | } | |
612 | ||
65f27f38 | 613 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 614 | { |
65f27f38 DH |
615 | struct rpc_xprt *xprt = |
616 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 617 | |
a246b010 | 618 | xprt->ops->close(xprt); |
66af1e55 | 619 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
1da177e4 LT |
620 | xprt_release_write(xprt, NULL); |
621 | } | |
622 | ||
9903cd1c | 623 | /** |
62da3b24 | 624 | * xprt_disconnect_done - mark a transport as disconnected |
9903cd1c CL |
625 | * @xprt: transport to flag for disconnect |
626 | * | |
1da177e4 | 627 | */ |
62da3b24 | 628 | void xprt_disconnect_done(struct rpc_xprt *xprt) |
1da177e4 | 629 | { |
46121cf7 | 630 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 631 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 632 | xprt_clear_connected(xprt); |
2a491991 | 633 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
4a0f8c04 | 634 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 635 | } |
62da3b24 | 636 | EXPORT_SYMBOL_GPL(xprt_disconnect_done); |
1da177e4 | 637 | |
66af1e55 TM |
638 | /** |
639 | * xprt_force_disconnect - force a transport to disconnect | |
640 | * @xprt: transport to disconnect | |
641 | * | |
642 | */ | |
643 | void xprt_force_disconnect(struct rpc_xprt *xprt) | |
644 | { | |
645 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
646 | spin_lock_bh(&xprt->transport_lock); | |
647 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
648 | /* Try to schedule an autoclose RPC call */ | |
649 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
650 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 651 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
66af1e55 TM |
652 | spin_unlock_bh(&xprt->transport_lock); |
653 | } | |
66af1e55 | 654 | |
7c1d71cf TM |
655 | /** |
656 | * xprt_conditional_disconnect - force a transport to disconnect | |
657 | * @xprt: transport to disconnect | |
658 | * @cookie: 'connection cookie' | |
659 | * | |
660 | * This attempts to break the connection if and only if 'cookie' matches | |
661 | * the current transport 'connection cookie'. It ensures that we don't | |
662 | * try to break the connection more than once when we need to retransmit | |
663 | * a batch of RPC requests. | |
664 | * | |
665 | */ | |
666 | void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) | |
667 | { | |
668 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
669 | spin_lock_bh(&xprt->transport_lock); | |
670 | if (cookie != xprt->connect_cookie) | |
671 | goto out; | |
672 | if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) | |
673 | goto out; | |
674 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
675 | /* Try to schedule an autoclose RPC call */ | |
676 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
677 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 678 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
7c1d71cf TM |
679 | out: |
680 | spin_unlock_bh(&xprt->transport_lock); | |
681 | } | |
682 | ||
1da177e4 LT |
683 | static void |
684 | xprt_init_autodisconnect(unsigned long data) | |
685 | { | |
686 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
687 | ||
4a0f8c04 | 688 | spin_lock(&xprt->transport_lock); |
d19751e7 | 689 | if (!list_empty(&xprt->recv)) |
1da177e4 | 690 | goto out_abort; |
2226feb6 | 691 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 692 | goto out_abort; |
4a0f8c04 | 693 | spin_unlock(&xprt->transport_lock); |
f75e6745 TM |
694 | set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); |
695 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
1da177e4 LT |
696 | return; |
697 | out_abort: | |
4a0f8c04 | 698 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
699 | } |
700 | ||
9903cd1c CL |
701 | /** |
702 | * xprt_connect - schedule a transport connect operation | |
703 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
704 | * |
705 | */ | |
706 | void xprt_connect(struct rpc_task *task) | |
707 | { | |
ad2368d6 | 708 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 709 | |
46121cf7 | 710 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
711 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
712 | ||
ec739ef0 | 713 | if (!xprt_bound(xprt)) { |
01d37c42 | 714 | task->tk_status = -EAGAIN; |
1da177e4 LT |
715 | return; |
716 | } | |
717 | if (!xprt_lock_write(xprt, task)) | |
718 | return; | |
feb8ca37 TM |
719 | |
720 | if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) | |
721 | xprt->ops->close(xprt); | |
722 | ||
1da177e4 | 723 | if (xprt_connected(xprt)) |
a246b010 CL |
724 | xprt_release_write(xprt, task); |
725 | else { | |
87e3c055 | 726 | task->tk_rqstp->rq_bytes_sent = 0; |
a8ce4a8f | 727 | task->tk_timeout = task->tk_rqstp->rq_timeout; |
5d00837b | 728 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
0b9e7943 TM |
729 | |
730 | if (test_bit(XPRT_CLOSING, &xprt->state)) | |
731 | return; | |
732 | if (xprt_test_and_set_connecting(xprt)) | |
733 | return; | |
262ca07d | 734 | xprt->stat.connect_start = jiffies; |
1b092092 | 735 | xprt->ops->connect(xprt, task); |
1da177e4 | 736 | } |
1da177e4 LT |
737 | } |
738 | ||
9903cd1c | 739 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 | 740 | { |
ad2368d6 | 741 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 742 | |
cd983ef8 | 743 | if (task->tk_status == 0) { |
262ca07d CL |
744 | xprt->stat.connect_count++; |
745 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 746 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
747 | task->tk_pid); |
748 | return; | |
749 | } | |
750 | ||
1da177e4 | 751 | switch (task->tk_status) { |
0fe8d04e TM |
752 | case -ECONNREFUSED: |
753 | case -ECONNRESET: | |
754 | case -ECONNABORTED: | |
755 | case -ENETUNREACH: | |
756 | case -EHOSTUNREACH: | |
2a491991 TM |
757 | case -EAGAIN: |
758 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 759 | break; |
1da177e4 | 760 | case -ETIMEDOUT: |
46121cf7 CL |
761 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
762 | "out\n", task->tk_pid); | |
1da177e4 LT |
763 | break; |
764 | default: | |
46121cf7 CL |
765 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
766 | "server %s\n", task->tk_pid, -task->tk_status, | |
4e0038b6 | 767 | xprt->servername); |
23475d66 CL |
768 | xprt_release_write(xprt, task); |
769 | task->tk_status = -EIO; | |
1da177e4 | 770 | } |
1da177e4 LT |
771 | } |
772 | ||
9903cd1c CL |
773 | /** |
774 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
775 | * @xprt: transport on which the original request was transmitted | |
776 | * @xid: RPC XID of incoming reply | |
777 | * | |
1da177e4 | 778 | */ |
d8ed029d | 779 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 | 780 | { |
8f3a6de3 | 781 | struct rpc_rqst *entry; |
1da177e4 | 782 | |
8f3a6de3 | 783 | list_for_each_entry(entry, &xprt->recv, rq_list) |
262ca07d CL |
784 | if (entry->rq_xid == xid) |
785 | return entry; | |
46121cf7 CL |
786 | |
787 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
788 | ntohl(xid)); | |
262ca07d CL |
789 | xprt->stat.bad_xids++; |
790 | return NULL; | |
1da177e4 | 791 | } |
12444809 | 792 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 793 | |
bbc72cea | 794 | static void xprt_update_rtt(struct rpc_task *task) |
1570c1e4 CL |
795 | { |
796 | struct rpc_rqst *req = task->tk_rqstp; | |
797 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
95c96174 | 798 | unsigned int timer = task->tk_msg.rpc_proc->p_timer; |
d60dbb20 | 799 | long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); |
1570c1e4 CL |
800 | |
801 | if (timer) { | |
802 | if (req->rq_ntrans == 1) | |
ff839970 | 803 | rpc_update_rtt(rtt, timer, m); |
1570c1e4 CL |
804 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); |
805 | } | |
806 | } | |
807 | ||
9903cd1c CL |
808 | /** |
809 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 810 | * @task: RPC request that recently completed |
9903cd1c CL |
811 | * @copied: actual number of bytes received from the transport |
812 | * | |
1570c1e4 | 813 | * Caller holds transport lock. |
1da177e4 | 814 | */ |
1570c1e4 | 815 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 816 | { |
1570c1e4 | 817 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 818 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 819 | |
1570c1e4 CL |
820 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
821 | task->tk_pid, ntohl(req->rq_xid), copied); | |
1da177e4 | 822 | |
fda13939 | 823 | xprt->stat.recvs++; |
d60dbb20 | 824 | req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); |
bbc72cea CL |
825 | if (xprt->ops->timer != NULL) |
826 | xprt_update_rtt(task); | |
ef759a2e | 827 | |
1da177e4 | 828 | list_del_init(&req->rq_list); |
1e799b67 | 829 | req->rq_private_buf.len = copied; |
dd2b63d0 RL |
830 | /* Ensure all writes are done before we update */ |
831 | /* req->rq_reply_bytes_recvd */ | |
43ac3f29 | 832 | smp_wmb(); |
dd2b63d0 | 833 | req->rq_reply_bytes_recvd = copied; |
fda13939 | 834 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 835 | } |
12444809 | 836 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 837 | |
46c0ee8b | 838 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 839 | { |
46c0ee8b | 840 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
841 | struct rpc_xprt *xprt = req->rq_xprt; |
842 | ||
5d00837b TM |
843 | if (task->tk_status != -ETIMEDOUT) |
844 | return; | |
46121cf7 | 845 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 846 | |
5d00837b | 847 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 | 848 | if (!req->rq_reply_bytes_recvd) { |
46c0ee8b | 849 | if (xprt->ops->timer) |
6a24dfb6 | 850 | xprt->ops->timer(xprt, task); |
5d00837b TM |
851 | } else |
852 | task->tk_status = 0; | |
853 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
854 | } |
855 | ||
4cfc7e60 RI |
856 | static inline int xprt_has_timer(struct rpc_xprt *xprt) |
857 | { | |
858 | return xprt->idle_timeout != 0; | |
859 | } | |
860 | ||
9903cd1c CL |
861 | /** |
862 | * xprt_prepare_transmit - reserve the transport before sending a request | |
863 | * @task: RPC task about to send a request | |
864 | * | |
1da177e4 | 865 | */ |
90051ea7 | 866 | bool xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
867 | { |
868 | struct rpc_rqst *req = task->tk_rqstp; | |
869 | struct rpc_xprt *xprt = req->rq_xprt; | |
90051ea7 | 870 | bool ret = false; |
1da177e4 | 871 | |
46121cf7 | 872 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 873 | |
4a0f8c04 | 874 | spin_lock_bh(&xprt->transport_lock); |
8a19a0b6 TM |
875 | if (!req->rq_bytes_sent) { |
876 | if (req->rq_reply_bytes_recvd) { | |
877 | task->tk_status = req->rq_reply_bytes_recvd; | |
878 | goto out_unlock; | |
879 | } | |
880 | if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) | |
881 | && xprt_connected(xprt) | |
882 | && req->rq_connect_cookie == xprt->connect_cookie) { | |
883 | xprt->ops->set_retrans_timeout(task); | |
884 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
885 | goto out_unlock; | |
886 | } | |
1da177e4 | 887 | } |
90051ea7 TM |
888 | if (!xprt->ops->reserve_xprt(xprt, task)) { |
889 | task->tk_status = -EAGAIN; | |
890 | goto out_unlock; | |
891 | } | |
892 | ret = true; | |
1da177e4 | 893 | out_unlock: |
4a0f8c04 | 894 | spin_unlock_bh(&xprt->transport_lock); |
90051ea7 | 895 | return ret; |
1da177e4 LT |
896 | } |
897 | ||
e0ab53de | 898 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 899 | { |
343952fa | 900 | xprt_release_write(task->tk_rqstp->rq_xprt, task); |
5e5ce5be TM |
901 | } |
902 | ||
9903cd1c CL |
903 | /** |
904 | * xprt_transmit - send an RPC request on a transport | |
905 | * @task: controlling RPC task | |
906 | * | |
907 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
908 | */ | |
909 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 910 | { |
1da177e4 LT |
911 | struct rpc_rqst *req = task->tk_rqstp; |
912 | struct rpc_xprt *xprt = req->rq_xprt; | |
15a45206 | 913 | int status, numreqs; |
1da177e4 | 914 | |
46121cf7 | 915 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 916 | |
dd2b63d0 | 917 | if (!req->rq_reply_bytes_recvd) { |
55ae1aab RL |
918 | if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { |
919 | /* | |
920 | * Add to the list only if we're expecting a reply | |
921 | */ | |
4a0f8c04 | 922 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
923 | /* Update the softirq receive buffer */ |
924 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
925 | sizeof(req->rq_private_buf)); | |
926 | /* Add request to the receive list */ | |
927 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 928 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 929 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
930 | /* Turn off autodisconnect */ |
931 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
932 | } |
933 | } else if (!req->rq_bytes_sent) | |
934 | return; | |
935 | ||
ff839970 | 936 | req->rq_xtime = ktime_get(); |
a246b010 | 937 | status = xprt->ops->send_request(task); |
c8485e4d TM |
938 | if (status != 0) { |
939 | task->tk_status = status; | |
940 | return; | |
941 | } | |
262ca07d | 942 | |
c8485e4d | 943 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
468f8613 | 944 | task->tk_flags |= RPC_TASK_SENT; |
c8485e4d | 945 | spin_lock_bh(&xprt->transport_lock); |
262ca07d | 946 | |
c8485e4d | 947 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 948 | |
15a45206 AA |
949 | numreqs = atomic_read(&xprt->num_reqs); |
950 | if (numreqs > xprt->stat.max_slots) | |
951 | xprt->stat.max_slots = numreqs; | |
c8485e4d TM |
952 | xprt->stat.sends++; |
953 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
954 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
15a45206 AA |
955 | xprt->stat.sending_u += xprt->sending.qlen; |
956 | xprt->stat.pending_u += xprt->pending.qlen; | |
1da177e4 | 957 | |
c8485e4d TM |
958 | /* Don't race with disconnect */ |
959 | if (!xprt_connected(xprt)) | |
960 | task->tk_status = -ENOTCONN; | |
0a660521 | 961 | else { |
55ae1aab RL |
962 | /* |
963 | * Sleep on the pending queue since | |
964 | * we're expecting a reply. | |
965 | */ | |
0a660521 TM |
966 | if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) |
967 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
968 | req->rq_connect_cookie = xprt->connect_cookie; | |
55ae1aab | 969 | } |
c8485e4d | 970 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
971 | } |
972 | ||
ba60eb25 TM |
973 | static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) |
974 | { | |
975 | set_bit(XPRT_CONGESTED, &xprt->state); | |
976 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
977 | } | |
978 | ||
979 | static void xprt_wake_up_backlog(struct rpc_xprt *xprt) | |
980 | { | |
981 | if (rpc_wake_up_next(&xprt->backlog) == NULL) | |
982 | clear_bit(XPRT_CONGESTED, &xprt->state); | |
983 | } | |
984 | ||
985 | static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) | |
986 | { | |
987 | bool ret = false; | |
988 | ||
989 | if (!test_bit(XPRT_CONGESTED, &xprt->state)) | |
990 | goto out; | |
991 | spin_lock(&xprt->reserve_lock); | |
992 | if (test_bit(XPRT_CONGESTED, &xprt->state)) { | |
993 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
994 | ret = true; | |
995 | } | |
996 | spin_unlock(&xprt->reserve_lock); | |
997 | out: | |
998 | return ret; | |
999 | } | |
1000 | ||
d9ba131d TM |
1001 | static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) |
1002 | { | |
1003 | struct rpc_rqst *req = ERR_PTR(-EAGAIN); | |
1004 | ||
1005 | if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) | |
1006 | goto out; | |
1007 | req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); | |
1008 | if (req != NULL) | |
1009 | goto out; | |
1010 | atomic_dec(&xprt->num_reqs); | |
1011 | req = ERR_PTR(-ENOMEM); | |
1012 | out: | |
1013 | return req; | |
1014 | } | |
1015 | ||
1016 | static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
1017 | { | |
1018 | if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { | |
1019 | kfree(req); | |
1020 | return true; | |
1021 | } | |
1022 | return false; | |
1023 | } | |
1024 | ||
f39c1bfb | 1025 | void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 | 1026 | { |
d9ba131d | 1027 | struct rpc_rqst *req; |
1da177e4 | 1028 | |
f39c1bfb | 1029 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 1030 | if (!list_empty(&xprt->free)) { |
d9ba131d TM |
1031 | req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); |
1032 | list_del(&req->rq_list); | |
1033 | goto out_init_req; | |
1034 | } | |
6b343099 | 1035 | req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN); |
d9ba131d TM |
1036 | if (!IS_ERR(req)) |
1037 | goto out_init_req; | |
1038 | switch (PTR_ERR(req)) { | |
1039 | case -ENOMEM: | |
d9ba131d TM |
1040 | dprintk("RPC: dynamic allocation of request slot " |
1041 | "failed! Retrying\n"); | |
1afeaf5c | 1042 | task->tk_status = -ENOMEM; |
d9ba131d TM |
1043 | break; |
1044 | case -EAGAIN: | |
ba60eb25 | 1045 | xprt_add_backlog(xprt, task); |
d9ba131d | 1046 | dprintk("RPC: waiting for request slot\n"); |
1afeaf5c TM |
1047 | default: |
1048 | task->tk_status = -EAGAIN; | |
1da177e4 | 1049 | } |
f39c1bfb | 1050 | spin_unlock(&xprt->reserve_lock); |
d9ba131d TM |
1051 | return; |
1052 | out_init_req: | |
1053 | task->tk_status = 0; | |
1054 | task->tk_rqstp = req; | |
1055 | xprt_request_init(task, xprt); | |
f39c1bfb TM |
1056 | spin_unlock(&xprt->reserve_lock); |
1057 | } | |
1058 | EXPORT_SYMBOL_GPL(xprt_alloc_slot); | |
1059 | ||
1060 | void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) | |
1061 | { | |
1062 | /* Note: grabbing the xprt_lock_write() ensures that we throttle | |
1063 | * new slot allocation if the transport is congested (i.e. when | |
1064 | * reconnecting a stream transport or when out of socket write | |
1065 | * buffer space). | |
1066 | */ | |
1067 | if (xprt_lock_write(xprt, task)) { | |
1068 | xprt_alloc_slot(xprt, task); | |
1069 | xprt_release_write(xprt, task); | |
1070 | } | |
1da177e4 | 1071 | } |
f39c1bfb | 1072 | EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot); |
1da177e4 | 1073 | |
ee5ebe85 TM |
1074 | static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) |
1075 | { | |
ee5ebe85 | 1076 | spin_lock(&xprt->reserve_lock); |
c25573b5 TM |
1077 | if (!xprt_dynamic_free_slot(xprt, req)) { |
1078 | memset(req, 0, sizeof(*req)); /* mark unused */ | |
1079 | list_add(&req->rq_list, &xprt->free); | |
1080 | } | |
ba60eb25 | 1081 | xprt_wake_up_backlog(xprt); |
ee5ebe85 TM |
1082 | spin_unlock(&xprt->reserve_lock); |
1083 | } | |
1084 | ||
21de0a95 TM |
1085 | static void xprt_free_all_slots(struct rpc_xprt *xprt) |
1086 | { | |
1087 | struct rpc_rqst *req; | |
1088 | while (!list_empty(&xprt->free)) { | |
1089 | req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); | |
1090 | list_del(&req->rq_list); | |
1091 | kfree(req); | |
1092 | } | |
1093 | } | |
1094 | ||
d9ba131d TM |
1095 | struct rpc_xprt *xprt_alloc(struct net *net, size_t size, |
1096 | unsigned int num_prealloc, | |
1097 | unsigned int max_alloc) | |
bd1722d4 PE |
1098 | { |
1099 | struct rpc_xprt *xprt; | |
21de0a95 TM |
1100 | struct rpc_rqst *req; |
1101 | int i; | |
bd1722d4 PE |
1102 | |
1103 | xprt = kzalloc(size, GFP_KERNEL); | |
1104 | if (xprt == NULL) | |
1105 | goto out; | |
1106 | ||
21de0a95 TM |
1107 | xprt_init(xprt, net); |
1108 | ||
1109 | for (i = 0; i < num_prealloc; i++) { | |
1110 | req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); | |
1111 | if (!req) | |
8313164c | 1112 | goto out_free; |
21de0a95 TM |
1113 | list_add(&req->rq_list, &xprt->free); |
1114 | } | |
d9ba131d TM |
1115 | if (max_alloc > num_prealloc) |
1116 | xprt->max_reqs = max_alloc; | |
1117 | else | |
1118 | xprt->max_reqs = num_prealloc; | |
1119 | xprt->min_reqs = num_prealloc; | |
1120 | atomic_set(&xprt->num_reqs, num_prealloc); | |
bd1722d4 PE |
1121 | |
1122 | return xprt; | |
1123 | ||
1124 | out_free: | |
21de0a95 | 1125 | xprt_free(xprt); |
bd1722d4 PE |
1126 | out: |
1127 | return NULL; | |
1128 | } | |
1129 | EXPORT_SYMBOL_GPL(xprt_alloc); | |
1130 | ||
e204e621 PE |
1131 | void xprt_free(struct rpc_xprt *xprt) |
1132 | { | |
37aa2133 | 1133 | put_net(xprt->xprt_net); |
21de0a95 | 1134 | xprt_free_all_slots(xprt); |
e204e621 PE |
1135 | kfree(xprt); |
1136 | } | |
1137 | EXPORT_SYMBOL_GPL(xprt_free); | |
1138 | ||
9903cd1c CL |
1139 | /** |
1140 | * xprt_reserve - allocate an RPC request slot | |
1141 | * @task: RPC task requesting a slot allocation | |
1142 | * | |
ba60eb25 TM |
1143 | * If the transport is marked as being congested, or if no more |
1144 | * slots are available, place the task on the transport's | |
9903cd1c CL |
1145 | * backlog queue. |
1146 | */ | |
1147 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 | 1148 | { |
45bc0dce | 1149 | struct rpc_xprt *xprt; |
1da177e4 | 1150 | |
43cedbf0 TM |
1151 | task->tk_status = 0; |
1152 | if (task->tk_rqstp != NULL) | |
1153 | return; | |
1154 | ||
43cedbf0 TM |
1155 | task->tk_timeout = 0; |
1156 | task->tk_status = -EAGAIN; | |
45bc0dce TM |
1157 | rcu_read_lock(); |
1158 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
ba60eb25 TM |
1159 | if (!xprt_throttle_congested(xprt, task)) |
1160 | xprt->ops->alloc_slot(xprt, task); | |
1161 | rcu_read_unlock(); | |
1162 | } | |
1163 | ||
1164 | /** | |
1165 | * xprt_retry_reserve - allocate an RPC request slot | |
1166 | * @task: RPC task requesting a slot allocation | |
1167 | * | |
1168 | * If no more slots are available, place the task on the transport's | |
1169 | * backlog queue. | |
1170 | * Note that the only difference with xprt_reserve is that we now | |
1171 | * ignore the value of the XPRT_CONGESTED flag. | |
1172 | */ | |
1173 | void xprt_retry_reserve(struct rpc_task *task) | |
1174 | { | |
1175 | struct rpc_xprt *xprt; | |
1176 | ||
1177 | task->tk_status = 0; | |
1178 | if (task->tk_rqstp != NULL) | |
1179 | return; | |
1180 | ||
1181 | task->tk_timeout = 0; | |
1182 | task->tk_status = -EAGAIN; | |
1183 | rcu_read_lock(); | |
1184 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
f39c1bfb | 1185 | xprt->ops->alloc_slot(xprt, task); |
45bc0dce | 1186 | rcu_read_unlock(); |
1da177e4 LT |
1187 | } |
1188 | ||
d8ed029d | 1189 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 | 1190 | { |
0eae88f3 | 1191 | return (__force __be32)xprt->xid++; |
1da177e4 LT |
1192 | } |
1193 | ||
1194 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
1195 | { | |
63862b5b | 1196 | xprt->xid = prandom_u32(); |
1da177e4 LT |
1197 | } |
1198 | ||
9903cd1c | 1199 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
1200 | { |
1201 | struct rpc_rqst *req = task->tk_rqstp; | |
1202 | ||
d9ba131d | 1203 | INIT_LIST_HEAD(&req->rq_list); |
ba7392bb | 1204 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
1205 | req->rq_task = task; |
1206 | req->rq_xprt = xprt; | |
02107148 | 1207 | req->rq_buffer = NULL; |
1da177e4 | 1208 | req->rq_xid = xprt_alloc_xid(xprt); |
0a660521 | 1209 | req->rq_connect_cookie = xprt->connect_cookie - 1; |
92551948 TM |
1210 | req->rq_bytes_sent = 0; |
1211 | req->rq_snd_buf.len = 0; | |
1212 | req->rq_snd_buf.buflen = 0; | |
1213 | req->rq_rcv_buf.len = 0; | |
1214 | req->rq_rcv_buf.buflen = 0; | |
ead5e1c2 | 1215 | req->rq_release_snd_buf = NULL; |
da45828e | 1216 | xprt_reset_majortimeo(req); |
46121cf7 | 1217 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
1218 | req, ntohl(req->rq_xid)); |
1219 | } | |
1220 | ||
9903cd1c CL |
1221 | /** |
1222 | * xprt_release - release an RPC request slot | |
1223 | * @task: task which is finished with the slot | |
1224 | * | |
1da177e4 | 1225 | */ |
9903cd1c | 1226 | void xprt_release(struct rpc_task *task) |
1da177e4 | 1227 | { |
55ae1aab | 1228 | struct rpc_xprt *xprt; |
87ed5003 | 1229 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 | 1230 | |
87ed5003 TM |
1231 | if (req == NULL) { |
1232 | if (task->tk_client) { | |
1233 | rcu_read_lock(); | |
1234 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
1235 | if (xprt->snd_task == task) | |
1236 | xprt_release_write(xprt, task); | |
1237 | rcu_read_unlock(); | |
1238 | } | |
1da177e4 | 1239 | return; |
87ed5003 | 1240 | } |
55ae1aab | 1241 | |
55ae1aab | 1242 | xprt = req->rq_xprt; |
0a702195 WAA |
1243 | if (task->tk_ops->rpc_count_stats != NULL) |
1244 | task->tk_ops->rpc_count_stats(task, task->tk_calldata); | |
1245 | else if (task->tk_client) | |
1246 | rpc_count_iostats(task, task->tk_client->cl_metrics); | |
4a0f8c04 | 1247 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 1248 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
1249 | if (xprt->ops->release_request) |
1250 | xprt->ops->release_request(task); | |
1da177e4 LT |
1251 | if (!list_empty(&req->rq_list)) |
1252 | list_del(&req->rq_list); | |
1253 | xprt->last_used = jiffies; | |
4cfc7e60 | 1254 | if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) |
a246b010 | 1255 | mod_timer(&xprt->timer, |
03bf4b70 | 1256 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1257 | spin_unlock_bh(&xprt->transport_lock); |
ee5ebe85 | 1258 | if (req->rq_buffer) |
55ae1aab | 1259 | xprt->ops->buf_free(req->rq_buffer); |
a17c2153 TM |
1260 | if (req->rq_cred != NULL) |
1261 | put_rpccred(req->rq_cred); | |
1da177e4 | 1262 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1263 | if (req->rq_release_snd_buf) |
1264 | req->rq_release_snd_buf(req); | |
55ae1aab | 1265 | |
46121cf7 | 1266 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
ee5ebe85 TM |
1267 | if (likely(!bc_prealloc(req))) |
1268 | xprt_free_slot(xprt, req); | |
1269 | else | |
c9acb42e | 1270 | xprt_free_bc_request(req); |
1da177e4 LT |
1271 | } |
1272 | ||
21de0a95 | 1273 | static void xprt_init(struct rpc_xprt *xprt, struct net *net) |
c2866763 | 1274 | { |
21de0a95 | 1275 | atomic_set(&xprt->count, 1); |
c2866763 CL |
1276 | |
1277 | spin_lock_init(&xprt->transport_lock); | |
1278 | spin_lock_init(&xprt->reserve_lock); | |
1279 | ||
1280 | INIT_LIST_HEAD(&xprt->free); | |
1281 | INIT_LIST_HEAD(&xprt->recv); | |
9e00abc3 | 1282 | #if defined(CONFIG_SUNRPC_BACKCHANNEL) |
f9acac1a RL |
1283 | spin_lock_init(&xprt->bc_pa_lock); |
1284 | INIT_LIST_HEAD(&xprt->bc_pa_list); | |
9e00abc3 | 1285 | #endif /* CONFIG_SUNRPC_BACKCHANNEL */ |
f9acac1a | 1286 | |
c2866763 CL |
1287 | xprt->last_used = jiffies; |
1288 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1289 | xprt->bind_index = 0; |
c2866763 CL |
1290 | |
1291 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1292 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
34006cee | 1293 | rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); |
c2866763 CL |
1294 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); |
1295 | ||
c2866763 CL |
1296 | xprt_init_xid(xprt); |
1297 | ||
21de0a95 | 1298 | xprt->xprt_net = get_net(net); |
8d9266ff TM |
1299 | } |
1300 | ||
1301 | /** | |
1302 | * xprt_create_transport - create an RPC transport | |
1303 | * @args: rpc transport creation arguments | |
1304 | * | |
1305 | */ | |
1306 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) | |
1307 | { | |
1308 | struct rpc_xprt *xprt; | |
1309 | struct xprt_class *t; | |
1310 | ||
1311 | spin_lock(&xprt_list_lock); | |
1312 | list_for_each_entry(t, &xprt_list, list) { | |
1313 | if (t->ident == args->ident) { | |
1314 | spin_unlock(&xprt_list_lock); | |
1315 | goto found; | |
1316 | } | |
1317 | } | |
1318 | spin_unlock(&xprt_list_lock); | |
1319 | printk(KERN_ERR "RPC: transport (%d) not supported\n", args->ident); | |
1320 | return ERR_PTR(-EIO); | |
1321 | ||
1322 | found: | |
1323 | xprt = t->setup(args); | |
1324 | if (IS_ERR(xprt)) { | |
1325 | dprintk("RPC: xprt_create_transport: failed, %ld\n", | |
1326 | -PTR_ERR(xprt)); | |
21de0a95 | 1327 | goto out; |
8d9266ff | 1328 | } |
33d90ac0 BF |
1329 | if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) |
1330 | xprt->idle_timeout = 0; | |
21de0a95 TM |
1331 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
1332 | if (xprt_has_timer(xprt)) | |
1333 | setup_timer(&xprt->timer, xprt_init_autodisconnect, | |
1334 | (unsigned long)xprt); | |
1335 | else | |
1336 | init_timer(&xprt->timer); | |
4e0038b6 TM |
1337 | |
1338 | if (strlen(args->servername) > RPC_MAXNETNAMELEN) { | |
1339 | xprt_destroy(xprt); | |
1340 | return ERR_PTR(-EINVAL); | |
1341 | } | |
1342 | xprt->servername = kstrdup(args->servername, GFP_KERNEL); | |
1343 | if (xprt->servername == NULL) { | |
1344 | xprt_destroy(xprt); | |
1345 | return ERR_PTR(-ENOMEM); | |
1346 | } | |
1347 | ||
46121cf7 | 1348 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 | 1349 | xprt->max_reqs); |
21de0a95 | 1350 | out: |
c2866763 CL |
1351 | return xprt; |
1352 | } | |
1353 | ||
9903cd1c CL |
1354 | /** |
1355 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
a8de240a | 1356 | * @xprt: transport to destroy |
9903cd1c | 1357 | * |
1da177e4 | 1358 | */ |
a8de240a | 1359 | static void xprt_destroy(struct rpc_xprt *xprt) |
1da177e4 | 1360 | { |
46121cf7 | 1361 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 | 1362 | del_timer_sync(&xprt->timer); |
c8541ecd | 1363 | |
f6a1cc89 TM |
1364 | rpc_destroy_wait_queue(&xprt->binding); |
1365 | rpc_destroy_wait_queue(&xprt->pending); | |
1366 | rpc_destroy_wait_queue(&xprt->sending); | |
f6a1cc89 | 1367 | rpc_destroy_wait_queue(&xprt->backlog); |
c3ae62ae | 1368 | cancel_work_sync(&xprt->task_cleanup); |
4e0038b6 | 1369 | kfree(xprt->servername); |
c8541ecd CL |
1370 | /* |
1371 | * Tear down transport state and free the rpc_xprt | |
1372 | */ | |
a246b010 | 1373 | xprt->ops->destroy(xprt); |
6b6ca86b | 1374 | } |
1da177e4 | 1375 | |
6b6ca86b TM |
1376 | /** |
1377 | * xprt_put - release a reference to an RPC transport. | |
1378 | * @xprt: pointer to the transport | |
1379 | * | |
1380 | */ | |
1381 | void xprt_put(struct rpc_xprt *xprt) | |
1382 | { | |
a8de240a TM |
1383 | if (atomic_dec_and_test(&xprt->count)) |
1384 | xprt_destroy(xprt); | |
6b6ca86b | 1385 | } |