Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/net/sunrpc/xprt.c | |
3 | * | |
4 | * This is a generic RPC call interface supporting congestion avoidance, | |
5 | * and asynchronous calls. | |
6 | * | |
7 | * The interface works like this: | |
8 | * | |
9 | * - When a process places a call, it allocates a request slot if | |
10 | * one is available. Otherwise, it sleeps on the backlog queue | |
11 | * (xprt_reserve). | |
12 | * - Next, the caller puts together the RPC message, stuffs it into | |
55aa4f58 CL |
13 | * the request struct, and calls xprt_transmit(). |
14 | * - xprt_transmit sends the message and installs the caller on the | |
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 | ||
81c098af TT |
74 | /** |
75 | * xprt_register_transport - register a transport implementation | |
76 | * @transport: transport to register | |
77 | * | |
78 | * If a transport implementation is loaded as a kernel module, it can | |
79 | * call this interface to make itself known to the RPC client. | |
80 | * | |
81 | * Returns: | |
82 | * 0: transport successfully registered | |
83 | * -EEXIST: transport already registered | |
84 | * -EINVAL: transport module being unloaded | |
85 | */ | |
86 | int xprt_register_transport(struct xprt_class *transport) | |
87 | { | |
88 | struct xprt_class *t; | |
89 | int result; | |
90 | ||
91 | result = -EEXIST; | |
92 | spin_lock(&xprt_list_lock); | |
93 | list_for_each_entry(t, &xprt_list, list) { | |
94 | /* don't register the same transport class twice */ | |
4fa016eb | 95 | if (t->ident == transport->ident) |
81c098af TT |
96 | goto out; |
97 | } | |
98 | ||
c9f6cde6 DL |
99 | list_add_tail(&transport->list, &xprt_list); |
100 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
101 | transport->name); | |
102 | result = 0; | |
81c098af TT |
103 | |
104 | out: | |
105 | spin_unlock(&xprt_list_lock); | |
106 | return result; | |
107 | } | |
108 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
109 | ||
110 | /** | |
111 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 112 | * @transport: transport to unregister |
81c098af TT |
113 | * |
114 | * Returns: | |
115 | * 0: transport successfully unregistered | |
116 | * -ENOENT: transport never registered | |
117 | */ | |
118 | int xprt_unregister_transport(struct xprt_class *transport) | |
119 | { | |
120 | struct xprt_class *t; | |
121 | int result; | |
122 | ||
123 | result = 0; | |
124 | spin_lock(&xprt_list_lock); | |
125 | list_for_each_entry(t, &xprt_list, list) { | |
126 | if (t == transport) { | |
127 | printk(KERN_INFO | |
128 | "RPC: Unregistered %s transport module.\n", | |
129 | transport->name); | |
130 | list_del_init(&transport->list); | |
81c098af TT |
131 | goto out; |
132 | } | |
133 | } | |
134 | result = -ENOENT; | |
135 | ||
136 | out: | |
137 | spin_unlock(&xprt_list_lock); | |
138 | return result; | |
139 | } | |
140 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
141 | ||
441e3e24 TT |
142 | /** |
143 | * xprt_load_transport - load a transport implementation | |
144 | * @transport_name: transport to load | |
145 | * | |
146 | * Returns: | |
147 | * 0: transport successfully loaded | |
148 | * -ENOENT: transport module not available | |
149 | */ | |
150 | int xprt_load_transport(const char *transport_name) | |
151 | { | |
152 | struct xprt_class *t; | |
441e3e24 TT |
153 | int result; |
154 | ||
155 | result = 0; | |
156 | spin_lock(&xprt_list_lock); | |
157 | list_for_each_entry(t, &xprt_list, list) { | |
158 | if (strcmp(t->name, transport_name) == 0) { | |
159 | spin_unlock(&xprt_list_lock); | |
160 | goto out; | |
161 | } | |
162 | } | |
163 | spin_unlock(&xprt_list_lock); | |
ef7ffe8f | 164 | result = request_module("xprt%s", transport_name); |
441e3e24 TT |
165 | out: |
166 | return result; | |
167 | } | |
168 | EXPORT_SYMBOL_GPL(xprt_load_transport); | |
169 | ||
12a80469 CL |
170 | /** |
171 | * xprt_reserve_xprt - serialize write access to transports | |
172 | * @task: task that is requesting access to the transport | |
177c27bf | 173 | * @xprt: pointer to the target transport |
12a80469 CL |
174 | * |
175 | * This prevents mixing the payload of separate requests, and prevents | |
176 | * transport connects from colliding with writes. No congestion control | |
177 | * is provided. | |
178 | */ | |
43cedbf0 | 179 | int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
12a80469 | 180 | { |
12a80469 | 181 | struct rpc_rqst *req = task->tk_rqstp; |
34006cee | 182 | int priority; |
12a80469 CL |
183 | |
184 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
185 | if (task == xprt->snd_task) | |
186 | return 1; | |
12a80469 CL |
187 | goto out_sleep; |
188 | } | |
189 | xprt->snd_task = task; | |
92551948 | 190 | if (req != NULL) |
43cedbf0 | 191 | req->rq_ntrans++; |
4d4a76f3 | 192 | |
12a80469 CL |
193 | return 1; |
194 | ||
195 | out_sleep: | |
46121cf7 | 196 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
197 | task->tk_pid, xprt); |
198 | task->tk_timeout = 0; | |
199 | task->tk_status = -EAGAIN; | |
34006cee TM |
200 | if (req == NULL) |
201 | priority = RPC_PRIORITY_LOW; | |
202 | else if (!req->rq_ntrans) | |
203 | priority = RPC_PRIORITY_NORMAL; | |
12a80469 | 204 | else |
34006cee TM |
205 | priority = RPC_PRIORITY_HIGH; |
206 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
12a80469 CL |
207 | return 0; |
208 | } | |
12444809 | 209 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 210 | |
632e3bdc TM |
211 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
212 | { | |
213 | xprt->snd_task = NULL; | |
d19751e7 | 214 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { |
4e857c58 | 215 | smp_mb__before_atomic(); |
632e3bdc | 216 | clear_bit(XPRT_LOCKED, &xprt->state); |
4e857c58 | 217 | smp_mb__after_atomic(); |
632e3bdc | 218 | } else |
c1384c9c | 219 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
220 | } |
221 | ||
1da177e4 | 222 | /* |
12a80469 CL |
223 | * xprt_reserve_xprt_cong - serialize write access to transports |
224 | * @task: task that is requesting access to the transport | |
225 | * | |
226 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
227 | * integrated into the decision of whether a request is allowed to be | |
228 | * woken up and given access to the transport. | |
1da177e4 | 229 | */ |
43cedbf0 | 230 | int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
231 | { |
232 | struct rpc_rqst *req = task->tk_rqstp; | |
34006cee | 233 | int priority; |
1da177e4 | 234 | |
2226feb6 | 235 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
236 | if (task == xprt->snd_task) |
237 | return 1; | |
1da177e4 LT |
238 | goto out_sleep; |
239 | } | |
43cedbf0 TM |
240 | if (req == NULL) { |
241 | xprt->snd_task = task; | |
242 | return 1; | |
243 | } | |
12a80469 | 244 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 245 | xprt->snd_task = task; |
43cedbf0 | 246 | req->rq_ntrans++; |
1da177e4 LT |
247 | return 1; |
248 | } | |
632e3bdc | 249 | xprt_clear_locked(xprt); |
1da177e4 | 250 | out_sleep: |
46121cf7 | 251 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
252 | task->tk_timeout = 0; |
253 | task->tk_status = -EAGAIN; | |
34006cee TM |
254 | if (req == NULL) |
255 | priority = RPC_PRIORITY_LOW; | |
256 | else if (!req->rq_ntrans) | |
257 | priority = RPC_PRIORITY_NORMAL; | |
1da177e4 | 258 | else |
34006cee TM |
259 | priority = RPC_PRIORITY_HIGH; |
260 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
1da177e4 LT |
261 | return 0; |
262 | } | |
12444809 | 263 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 264 | |
12a80469 | 265 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
266 | { |
267 | int retval; | |
268 | ||
4a0f8c04 | 269 | spin_lock_bh(&xprt->transport_lock); |
43cedbf0 | 270 | retval = xprt->ops->reserve_xprt(xprt, task); |
4a0f8c04 | 271 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
272 | return retval; |
273 | } | |
274 | ||
961a828d | 275 | static bool __xprt_lock_write_func(struct rpc_task *task, void *data) |
49e9a890 | 276 | { |
961a828d | 277 | struct rpc_xprt *xprt = data; |
49e9a890 CL |
278 | struct rpc_rqst *req; |
279 | ||
49e9a890 CL |
280 | req = task->tk_rqstp; |
281 | xprt->snd_task = task; | |
92551948 | 282 | if (req) |
49e9a890 | 283 | req->rq_ntrans++; |
961a828d TM |
284 | return true; |
285 | } | |
49e9a890 | 286 | |
961a828d TM |
287 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
288 | { | |
289 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
290 | return; | |
291 | ||
292 | if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt)) | |
293 | return; | |
632e3bdc | 294 | xprt_clear_locked(xprt); |
49e9a890 CL |
295 | } |
296 | ||
961a828d | 297 | static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) |
1da177e4 | 298 | { |
961a828d | 299 | struct rpc_xprt *xprt = data; |
43cedbf0 | 300 | struct rpc_rqst *req; |
1da177e4 | 301 | |
43cedbf0 TM |
302 | req = task->tk_rqstp; |
303 | if (req == NULL) { | |
304 | xprt->snd_task = task; | |
961a828d | 305 | return true; |
43cedbf0 | 306 | } |
49e9a890 | 307 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 308 | xprt->snd_task = task; |
43cedbf0 | 309 | req->rq_ntrans++; |
961a828d | 310 | return true; |
1da177e4 | 311 | } |
961a828d TM |
312 | return false; |
313 | } | |
314 | ||
315 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
316 | { | |
317 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
318 | return; | |
319 | if (RPCXPRT_CONGESTED(xprt)) | |
320 | goto out_unlock; | |
321 | if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt)) | |
322 | return; | |
1da177e4 | 323 | out_unlock: |
632e3bdc | 324 | xprt_clear_locked(xprt); |
1da177e4 LT |
325 | } |
326 | ||
49e9a890 CL |
327 | /** |
328 | * xprt_release_xprt - allow other requests to use a transport | |
329 | * @xprt: transport with other tasks potentially waiting | |
330 | * @task: task that is releasing access to the transport | |
331 | * | |
332 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 333 | */ |
49e9a890 | 334 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
335 | { |
336 | if (xprt->snd_task == task) { | |
ee071eff TM |
337 | if (task != NULL) { |
338 | struct rpc_rqst *req = task->tk_rqstp; | |
339 | if (req != NULL) | |
340 | req->rq_bytes_sent = 0; | |
341 | } | |
632e3bdc | 342 | xprt_clear_locked(xprt); |
1da177e4 LT |
343 | __xprt_lock_write_next(xprt); |
344 | } | |
345 | } | |
12444809 | 346 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 347 | |
49e9a890 CL |
348 | /** |
349 | * xprt_release_xprt_cong - allow other requests to use a transport | |
350 | * @xprt: transport with other tasks potentially waiting | |
351 | * @task: task that is releasing access to the transport | |
352 | * | |
353 | * Note that "task" can be NULL. Another task is awoken to use the | |
354 | * transport if the transport's congestion window allows it. | |
355 | */ | |
356 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
357 | { | |
358 | if (xprt->snd_task == task) { | |
ee071eff TM |
359 | if (task != NULL) { |
360 | struct rpc_rqst *req = task->tk_rqstp; | |
361 | if (req != NULL) | |
362 | req->rq_bytes_sent = 0; | |
363 | } | |
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 | { | |
a4f0835c TM |
419 | struct rpc_rqst *req = task->tk_rqstp; |
420 | ||
421 | __xprt_put_cong(req->rq_xprt, req); | |
a58dd398 | 422 | } |
12444809 | 423 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 424 | |
46c0ee8b CL |
425 | /** |
426 | * xprt_adjust_cwnd - adjust transport congestion window | |
6a24dfb6 | 427 | * @xprt: pointer to xprt |
46c0ee8b CL |
428 | * @task: recently completed RPC request used to adjust window |
429 | * @result: result code of completed RPC request | |
430 | * | |
4f4cf5ad CL |
431 | * The transport code maintains an estimate on the maximum number of out- |
432 | * standing RPC requests, using a smoothed version of the congestion | |
433 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
434 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
435 | * halved; otherwise, it is incremented by 1/cwnd when | |
436 | * | |
437 | * - a reply is received and | |
438 | * - a full number of requests are outstanding and | |
439 | * - the congestion window hasn't been updated recently. | |
1da177e4 | 440 | */ |
6a24dfb6 | 441 | void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) |
1da177e4 | 442 | { |
46c0ee8b | 443 | struct rpc_rqst *req = task->tk_rqstp; |
46c0ee8b | 444 | unsigned long cwnd = xprt->cwnd; |
1da177e4 | 445 | |
1da177e4 LT |
446 | if (result >= 0 && cwnd <= xprt->cong) { |
447 | /* The (cwnd >> 1) term makes sure | |
448 | * the result gets rounded properly. */ | |
449 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
450 | if (cwnd > RPC_MAXCWND(xprt)) | |
451 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 452 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
453 | } else if (result == -ETIMEDOUT) { |
454 | cwnd >>= 1; | |
455 | if (cwnd < RPC_CWNDSCALE) | |
456 | cwnd = RPC_CWNDSCALE; | |
457 | } | |
46121cf7 | 458 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
459 | xprt->cong, xprt->cwnd, cwnd); |
460 | xprt->cwnd = cwnd; | |
46c0ee8b | 461 | __xprt_put_cong(xprt, req); |
1da177e4 | 462 | } |
12444809 | 463 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 464 | |
44fbac22 CL |
465 | /** |
466 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
467 | * @xprt: transport with waiting tasks | |
468 | * @status: result code to plant in each task before waking it | |
469 | * | |
470 | */ | |
471 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
472 | { | |
473 | if (status < 0) | |
474 | rpc_wake_up_status(&xprt->pending, status); | |
475 | else | |
476 | rpc_wake_up(&xprt->pending); | |
477 | } | |
12444809 | 478 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 479 | |
c7b2cae8 CL |
480 | /** |
481 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
482 | * @task: task to be put to sleep | |
0b80ae42 | 483 | * @action: function pointer to be executed after wait |
a9a6b52e TM |
484 | * |
485 | * Note that we only set the timer for the case of RPC_IS_SOFT(), since | |
486 | * we don't in general want to force a socket disconnection due to | |
487 | * an incomplete RPC call transmission. | |
c7b2cae8 | 488 | */ |
b6ddf64f | 489 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
490 | { |
491 | struct rpc_rqst *req = task->tk_rqstp; | |
492 | struct rpc_xprt *xprt = req->rq_xprt; | |
493 | ||
a9a6b52e | 494 | task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; |
b6ddf64f | 495 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 496 | } |
12444809 | 497 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
498 | |
499 | /** | |
500 | * xprt_write_space - wake the task waiting for transport output buffer space | |
501 | * @xprt: transport with waiting tasks | |
502 | * | |
503 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
504 | */ | |
505 | void xprt_write_space(struct rpc_xprt *xprt) | |
506 | { | |
c7b2cae8 CL |
507 | spin_lock_bh(&xprt->transport_lock); |
508 | if (xprt->snd_task) { | |
46121cf7 CL |
509 | dprintk("RPC: write space: waking waiting task on " |
510 | "xprt %p\n", xprt); | |
fda13939 | 511 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
512 | } |
513 | spin_unlock_bh(&xprt->transport_lock); | |
514 | } | |
12444809 | 515 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 516 | |
fe3aca29 CL |
517 | /** |
518 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
519 | * @task: task whose timeout is to be set | |
520 | * | |
521 | * Set a request's retransmit timeout based on the transport's | |
522 | * default timeout parameters. Used by transports that don't adjust | |
523 | * the retransmit timeout based on round-trip time estimation. | |
524 | */ | |
525 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
526 | { | |
527 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
528 | } | |
12444809 | 529 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 | 530 | |
2c53040f | 531 | /** |
fe3aca29 CL |
532 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout |
533 | * @task: task whose timeout is to be set | |
cca5172a | 534 | * |
fe3aca29 CL |
535 | * Set a request's retransmit timeout using the RTT estimator. |
536 | */ | |
537 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
538 | { | |
539 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
540 | struct rpc_clnt *clnt = task->tk_client; |
541 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 542 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 543 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
544 | |
545 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
546 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
547 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
548 | task->tk_timeout = max_timeout; | |
549 | } | |
12444809 | 550 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 551 | |
1da177e4 LT |
552 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
553 | { | |
ba7392bb | 554 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
555 | |
556 | req->rq_majortimeo = req->rq_timeout; | |
557 | if (to->to_exponential) | |
558 | req->rq_majortimeo <<= to->to_retries; | |
559 | else | |
560 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
561 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
562 | req->rq_majortimeo = to->to_maxval; | |
563 | req->rq_majortimeo += jiffies; | |
564 | } | |
565 | ||
9903cd1c CL |
566 | /** |
567 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
568 | * @req: RPC request containing parameters to use for the adjustment | |
569 | * | |
1da177e4 LT |
570 | */ |
571 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
572 | { | |
573 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 574 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
575 | int status = 0; |
576 | ||
577 | if (time_before(jiffies, req->rq_majortimeo)) { | |
578 | if (to->to_exponential) | |
579 | req->rq_timeout <<= 1; | |
580 | else | |
581 | req->rq_timeout += to->to_increment; | |
582 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
583 | req->rq_timeout = to->to_maxval; | |
584 | req->rq_retries++; | |
1da177e4 LT |
585 | } else { |
586 | req->rq_timeout = to->to_initval; | |
587 | req->rq_retries = 0; | |
588 | xprt_reset_majortimeo(req); | |
589 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 590 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 591 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 592 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
593 | status = -ETIMEDOUT; |
594 | } | |
595 | ||
596 | if (req->rq_timeout == 0) { | |
597 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
598 | req->rq_timeout = 5 * HZ; | |
599 | } | |
600 | return status; | |
601 | } | |
602 | ||
65f27f38 | 603 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 604 | { |
65f27f38 DH |
605 | struct rpc_xprt *xprt = |
606 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 607 | |
a246b010 | 608 | xprt->ops->close(xprt); |
66af1e55 | 609 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
1da177e4 LT |
610 | xprt_release_write(xprt, NULL); |
611 | } | |
612 | ||
9903cd1c | 613 | /** |
62da3b24 | 614 | * xprt_disconnect_done - mark a transport as disconnected |
9903cd1c CL |
615 | * @xprt: transport to flag for disconnect |
616 | * | |
1da177e4 | 617 | */ |
62da3b24 | 618 | void xprt_disconnect_done(struct rpc_xprt *xprt) |
1da177e4 | 619 | { |
46121cf7 | 620 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 621 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 622 | xprt_clear_connected(xprt); |
2a491991 | 623 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
4a0f8c04 | 624 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 625 | } |
62da3b24 | 626 | EXPORT_SYMBOL_GPL(xprt_disconnect_done); |
1da177e4 | 627 | |
66af1e55 TM |
628 | /** |
629 | * xprt_force_disconnect - force a transport to disconnect | |
630 | * @xprt: transport to disconnect | |
631 | * | |
632 | */ | |
633 | void xprt_force_disconnect(struct rpc_xprt *xprt) | |
634 | { | |
635 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
636 | spin_lock_bh(&xprt->transport_lock); | |
637 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
638 | /* Try to schedule an autoclose RPC call */ | |
639 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
640 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 641 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
66af1e55 TM |
642 | spin_unlock_bh(&xprt->transport_lock); |
643 | } | |
66af1e55 | 644 | |
7c1d71cf TM |
645 | /** |
646 | * xprt_conditional_disconnect - force a transport to disconnect | |
647 | * @xprt: transport to disconnect | |
648 | * @cookie: 'connection cookie' | |
649 | * | |
650 | * This attempts to break the connection if and only if 'cookie' matches | |
651 | * the current transport 'connection cookie'. It ensures that we don't | |
652 | * try to break the connection more than once when we need to retransmit | |
653 | * a batch of RPC requests. | |
654 | * | |
655 | */ | |
656 | void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) | |
657 | { | |
658 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
659 | spin_lock_bh(&xprt->transport_lock); | |
660 | if (cookie != xprt->connect_cookie) | |
661 | goto out; | |
662 | if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) | |
663 | goto out; | |
664 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
665 | /* Try to schedule an autoclose RPC call */ | |
666 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
667 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 668 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
7c1d71cf TM |
669 | out: |
670 | spin_unlock_bh(&xprt->transport_lock); | |
671 | } | |
672 | ||
1da177e4 LT |
673 | static void |
674 | xprt_init_autodisconnect(unsigned long data) | |
675 | { | |
676 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
677 | ||
4a0f8c04 | 678 | spin_lock(&xprt->transport_lock); |
d19751e7 | 679 | if (!list_empty(&xprt->recv)) |
1da177e4 | 680 | goto out_abort; |
2226feb6 | 681 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 682 | goto out_abort; |
4a0f8c04 | 683 | spin_unlock(&xprt->transport_lock); |
f75e6745 TM |
684 | set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); |
685 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
1da177e4 LT |
686 | return; |
687 | out_abort: | |
4a0f8c04 | 688 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
689 | } |
690 | ||
9903cd1c CL |
691 | /** |
692 | * xprt_connect - schedule a transport connect operation | |
693 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
694 | * |
695 | */ | |
696 | void xprt_connect(struct rpc_task *task) | |
697 | { | |
ad2368d6 | 698 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 699 | |
46121cf7 | 700 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
701 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
702 | ||
ec739ef0 | 703 | if (!xprt_bound(xprt)) { |
01d37c42 | 704 | task->tk_status = -EAGAIN; |
1da177e4 LT |
705 | return; |
706 | } | |
707 | if (!xprt_lock_write(xprt, task)) | |
708 | return; | |
feb8ca37 TM |
709 | |
710 | if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) | |
711 | xprt->ops->close(xprt); | |
712 | ||
1da177e4 | 713 | if (xprt_connected(xprt)) |
a246b010 CL |
714 | xprt_release_write(xprt, task); |
715 | else { | |
87e3c055 | 716 | task->tk_rqstp->rq_bytes_sent = 0; |
a8ce4a8f | 717 | task->tk_timeout = task->tk_rqstp->rq_timeout; |
5d00837b | 718 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
0b9e7943 TM |
719 | |
720 | if (test_bit(XPRT_CLOSING, &xprt->state)) | |
721 | return; | |
722 | if (xprt_test_and_set_connecting(xprt)) | |
723 | return; | |
262ca07d | 724 | xprt->stat.connect_start = jiffies; |
1b092092 | 725 | xprt->ops->connect(xprt, task); |
1da177e4 | 726 | } |
1da177e4 LT |
727 | } |
728 | ||
9903cd1c | 729 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 | 730 | { |
ad2368d6 | 731 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 732 | |
cd983ef8 | 733 | if (task->tk_status == 0) { |
262ca07d CL |
734 | xprt->stat.connect_count++; |
735 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 736 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
737 | task->tk_pid); |
738 | return; | |
739 | } | |
740 | ||
1da177e4 | 741 | switch (task->tk_status) { |
0fe8d04e TM |
742 | case -ECONNREFUSED: |
743 | case -ECONNRESET: | |
744 | case -ECONNABORTED: | |
745 | case -ENETUNREACH: | |
746 | case -EHOSTUNREACH: | |
2fc193cf | 747 | case -EPIPE: |
2a491991 TM |
748 | case -EAGAIN: |
749 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 750 | break; |
1da177e4 | 751 | case -ETIMEDOUT: |
46121cf7 CL |
752 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
753 | "out\n", task->tk_pid); | |
1da177e4 LT |
754 | break; |
755 | default: | |
46121cf7 CL |
756 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
757 | "server %s\n", task->tk_pid, -task->tk_status, | |
4e0038b6 | 758 | xprt->servername); |
23475d66 CL |
759 | xprt_release_write(xprt, task); |
760 | task->tk_status = -EIO; | |
1da177e4 | 761 | } |
1da177e4 LT |
762 | } |
763 | ||
9903cd1c CL |
764 | /** |
765 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
766 | * @xprt: transport on which the original request was transmitted | |
767 | * @xid: RPC XID of incoming reply | |
768 | * | |
1da177e4 | 769 | */ |
d8ed029d | 770 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 | 771 | { |
8f3a6de3 | 772 | struct rpc_rqst *entry; |
1da177e4 | 773 | |
8f3a6de3 | 774 | list_for_each_entry(entry, &xprt->recv, rq_list) |
262ca07d CL |
775 | if (entry->rq_xid == xid) |
776 | return entry; | |
46121cf7 CL |
777 | |
778 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
779 | ntohl(xid)); | |
262ca07d CL |
780 | xprt->stat.bad_xids++; |
781 | return NULL; | |
1da177e4 | 782 | } |
12444809 | 783 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 784 | |
bbc72cea | 785 | static void xprt_update_rtt(struct rpc_task *task) |
1570c1e4 CL |
786 | { |
787 | struct rpc_rqst *req = task->tk_rqstp; | |
788 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
95c96174 | 789 | unsigned int timer = task->tk_msg.rpc_proc->p_timer; |
d60dbb20 | 790 | long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); |
1570c1e4 CL |
791 | |
792 | if (timer) { | |
793 | if (req->rq_ntrans == 1) | |
ff839970 | 794 | rpc_update_rtt(rtt, timer, m); |
1570c1e4 CL |
795 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); |
796 | } | |
797 | } | |
798 | ||
9903cd1c CL |
799 | /** |
800 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 801 | * @task: RPC request that recently completed |
9903cd1c CL |
802 | * @copied: actual number of bytes received from the transport |
803 | * | |
1570c1e4 | 804 | * Caller holds transport lock. |
1da177e4 | 805 | */ |
1570c1e4 | 806 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 807 | { |
1570c1e4 | 808 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 809 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 810 | |
1570c1e4 CL |
811 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
812 | task->tk_pid, ntohl(req->rq_xid), copied); | |
1da177e4 | 813 | |
fda13939 | 814 | xprt->stat.recvs++; |
d60dbb20 | 815 | req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); |
bbc72cea CL |
816 | if (xprt->ops->timer != NULL) |
817 | xprt_update_rtt(task); | |
ef759a2e | 818 | |
1da177e4 | 819 | list_del_init(&req->rq_list); |
1e799b67 | 820 | req->rq_private_buf.len = copied; |
dd2b63d0 RL |
821 | /* Ensure all writes are done before we update */ |
822 | /* req->rq_reply_bytes_recvd */ | |
43ac3f29 | 823 | smp_wmb(); |
dd2b63d0 | 824 | req->rq_reply_bytes_recvd = copied; |
fda13939 | 825 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 826 | } |
12444809 | 827 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 828 | |
46c0ee8b | 829 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 830 | { |
46c0ee8b | 831 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
832 | struct rpc_xprt *xprt = req->rq_xprt; |
833 | ||
5d00837b TM |
834 | if (task->tk_status != -ETIMEDOUT) |
835 | return; | |
46121cf7 | 836 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 837 | |
5d00837b | 838 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 | 839 | if (!req->rq_reply_bytes_recvd) { |
46c0ee8b | 840 | if (xprt->ops->timer) |
6a24dfb6 | 841 | xprt->ops->timer(xprt, task); |
5d00837b TM |
842 | } else |
843 | task->tk_status = 0; | |
844 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
845 | } |
846 | ||
4cfc7e60 RI |
847 | static inline int xprt_has_timer(struct rpc_xprt *xprt) |
848 | { | |
849 | return xprt->idle_timeout != 0; | |
850 | } | |
851 | ||
9903cd1c CL |
852 | /** |
853 | * xprt_prepare_transmit - reserve the transport before sending a request | |
854 | * @task: RPC task about to send a request | |
855 | * | |
1da177e4 | 856 | */ |
90051ea7 | 857 | bool xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
858 | { |
859 | struct rpc_rqst *req = task->tk_rqstp; | |
860 | struct rpc_xprt *xprt = req->rq_xprt; | |
90051ea7 | 861 | bool ret = false; |
1da177e4 | 862 | |
46121cf7 | 863 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 864 | |
4a0f8c04 | 865 | spin_lock_bh(&xprt->transport_lock); |
8a19a0b6 TM |
866 | if (!req->rq_bytes_sent) { |
867 | if (req->rq_reply_bytes_recvd) { | |
868 | task->tk_status = req->rq_reply_bytes_recvd; | |
869 | goto out_unlock; | |
870 | } | |
871 | if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) | |
872 | && xprt_connected(xprt) | |
873 | && req->rq_connect_cookie == xprt->connect_cookie) { | |
874 | xprt->ops->set_retrans_timeout(task); | |
875 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
876 | goto out_unlock; | |
877 | } | |
1da177e4 | 878 | } |
90051ea7 TM |
879 | if (!xprt->ops->reserve_xprt(xprt, task)) { |
880 | task->tk_status = -EAGAIN; | |
881 | goto out_unlock; | |
882 | } | |
883 | ret = true; | |
1da177e4 | 884 | out_unlock: |
4a0f8c04 | 885 | spin_unlock_bh(&xprt->transport_lock); |
90051ea7 | 886 | return ret; |
1da177e4 LT |
887 | } |
888 | ||
e0ab53de | 889 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 890 | { |
343952fa | 891 | xprt_release_write(task->tk_rqstp->rq_xprt, task); |
5e5ce5be TM |
892 | } |
893 | ||
9903cd1c CL |
894 | /** |
895 | * xprt_transmit - send an RPC request on a transport | |
896 | * @task: controlling RPC task | |
897 | * | |
898 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
899 | */ | |
900 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 901 | { |
1da177e4 LT |
902 | struct rpc_rqst *req = task->tk_rqstp; |
903 | struct rpc_xprt *xprt = req->rq_xprt; | |
15a45206 | 904 | int status, numreqs; |
1da177e4 | 905 | |
46121cf7 | 906 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 907 | |
dd2b63d0 | 908 | if (!req->rq_reply_bytes_recvd) { |
55ae1aab RL |
909 | if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { |
910 | /* | |
911 | * Add to the list only if we're expecting a reply | |
912 | */ | |
4a0f8c04 | 913 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
914 | /* Update the softirq receive buffer */ |
915 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
916 | sizeof(req->rq_private_buf)); | |
917 | /* Add request to the receive list */ | |
918 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 919 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 920 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
921 | /* Turn off autodisconnect */ |
922 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
923 | } |
924 | } else if (!req->rq_bytes_sent) | |
925 | return; | |
926 | ||
ff839970 | 927 | req->rq_xtime = ktime_get(); |
a246b010 | 928 | status = xprt->ops->send_request(task); |
c8485e4d TM |
929 | if (status != 0) { |
930 | task->tk_status = status; | |
931 | return; | |
932 | } | |
262ca07d | 933 | |
c8485e4d | 934 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
468f8613 | 935 | task->tk_flags |= RPC_TASK_SENT; |
c8485e4d | 936 | spin_lock_bh(&xprt->transport_lock); |
262ca07d | 937 | |
c8485e4d | 938 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 939 | |
15a45206 AA |
940 | numreqs = atomic_read(&xprt->num_reqs); |
941 | if (numreqs > xprt->stat.max_slots) | |
942 | xprt->stat.max_slots = numreqs; | |
c8485e4d TM |
943 | xprt->stat.sends++; |
944 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
945 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
15a45206 AA |
946 | xprt->stat.sending_u += xprt->sending.qlen; |
947 | xprt->stat.pending_u += xprt->pending.qlen; | |
1da177e4 | 948 | |
c8485e4d TM |
949 | /* Don't race with disconnect */ |
950 | if (!xprt_connected(xprt)) | |
951 | task->tk_status = -ENOTCONN; | |
0a660521 | 952 | else { |
55ae1aab RL |
953 | /* |
954 | * Sleep on the pending queue since | |
955 | * we're expecting a reply. | |
956 | */ | |
0a660521 TM |
957 | if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) |
958 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
959 | req->rq_connect_cookie = xprt->connect_cookie; | |
55ae1aab | 960 | } |
c8485e4d | 961 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
962 | } |
963 | ||
ba60eb25 TM |
964 | static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) |
965 | { | |
966 | set_bit(XPRT_CONGESTED, &xprt->state); | |
967 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
968 | } | |
969 | ||
970 | static void xprt_wake_up_backlog(struct rpc_xprt *xprt) | |
971 | { | |
972 | if (rpc_wake_up_next(&xprt->backlog) == NULL) | |
973 | clear_bit(XPRT_CONGESTED, &xprt->state); | |
974 | } | |
975 | ||
976 | static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) | |
977 | { | |
978 | bool ret = false; | |
979 | ||
980 | if (!test_bit(XPRT_CONGESTED, &xprt->state)) | |
981 | goto out; | |
982 | spin_lock(&xprt->reserve_lock); | |
983 | if (test_bit(XPRT_CONGESTED, &xprt->state)) { | |
984 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
985 | ret = true; | |
986 | } | |
987 | spin_unlock(&xprt->reserve_lock); | |
988 | out: | |
989 | return ret; | |
990 | } | |
991 | ||
d9ba131d TM |
992 | static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) |
993 | { | |
994 | struct rpc_rqst *req = ERR_PTR(-EAGAIN); | |
995 | ||
996 | if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) | |
997 | goto out; | |
998 | req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); | |
999 | if (req != NULL) | |
1000 | goto out; | |
1001 | atomic_dec(&xprt->num_reqs); | |
1002 | req = ERR_PTR(-ENOMEM); | |
1003 | out: | |
1004 | return req; | |
1005 | } | |
1006 | ||
1007 | static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
1008 | { | |
1009 | if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { | |
1010 | kfree(req); | |
1011 | return true; | |
1012 | } | |
1013 | return false; | |
1014 | } | |
1015 | ||
f39c1bfb | 1016 | void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 | 1017 | { |
d9ba131d | 1018 | struct rpc_rqst *req; |
1da177e4 | 1019 | |
f39c1bfb | 1020 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 1021 | if (!list_empty(&xprt->free)) { |
d9ba131d TM |
1022 | req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); |
1023 | list_del(&req->rq_list); | |
1024 | goto out_init_req; | |
1025 | } | |
6b343099 | 1026 | req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN); |
d9ba131d TM |
1027 | if (!IS_ERR(req)) |
1028 | goto out_init_req; | |
1029 | switch (PTR_ERR(req)) { | |
1030 | case -ENOMEM: | |
d9ba131d TM |
1031 | dprintk("RPC: dynamic allocation of request slot " |
1032 | "failed! Retrying\n"); | |
1afeaf5c | 1033 | task->tk_status = -ENOMEM; |
d9ba131d TM |
1034 | break; |
1035 | case -EAGAIN: | |
ba60eb25 | 1036 | xprt_add_backlog(xprt, task); |
d9ba131d | 1037 | dprintk("RPC: waiting for request slot\n"); |
1afeaf5c TM |
1038 | default: |
1039 | task->tk_status = -EAGAIN; | |
1da177e4 | 1040 | } |
f39c1bfb | 1041 | spin_unlock(&xprt->reserve_lock); |
d9ba131d TM |
1042 | return; |
1043 | out_init_req: | |
1044 | task->tk_status = 0; | |
1045 | task->tk_rqstp = req; | |
1046 | xprt_request_init(task, xprt); | |
f39c1bfb TM |
1047 | spin_unlock(&xprt->reserve_lock); |
1048 | } | |
1049 | EXPORT_SYMBOL_GPL(xprt_alloc_slot); | |
1050 | ||
1051 | void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) | |
1052 | { | |
1053 | /* Note: grabbing the xprt_lock_write() ensures that we throttle | |
1054 | * new slot allocation if the transport is congested (i.e. when | |
1055 | * reconnecting a stream transport or when out of socket write | |
1056 | * buffer space). | |
1057 | */ | |
1058 | if (xprt_lock_write(xprt, task)) { | |
1059 | xprt_alloc_slot(xprt, task); | |
1060 | xprt_release_write(xprt, task); | |
1061 | } | |
1da177e4 | 1062 | } |
f39c1bfb | 1063 | EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot); |
1da177e4 | 1064 | |
ee5ebe85 TM |
1065 | static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) |
1066 | { | |
ee5ebe85 | 1067 | spin_lock(&xprt->reserve_lock); |
c25573b5 TM |
1068 | if (!xprt_dynamic_free_slot(xprt, req)) { |
1069 | memset(req, 0, sizeof(*req)); /* mark unused */ | |
1070 | list_add(&req->rq_list, &xprt->free); | |
1071 | } | |
ba60eb25 | 1072 | xprt_wake_up_backlog(xprt); |
ee5ebe85 TM |
1073 | spin_unlock(&xprt->reserve_lock); |
1074 | } | |
1075 | ||
21de0a95 TM |
1076 | static void xprt_free_all_slots(struct rpc_xprt *xprt) |
1077 | { | |
1078 | struct rpc_rqst *req; | |
1079 | while (!list_empty(&xprt->free)) { | |
1080 | req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); | |
1081 | list_del(&req->rq_list); | |
1082 | kfree(req); | |
1083 | } | |
1084 | } | |
1085 | ||
d9ba131d TM |
1086 | struct rpc_xprt *xprt_alloc(struct net *net, size_t size, |
1087 | unsigned int num_prealloc, | |
1088 | unsigned int max_alloc) | |
bd1722d4 PE |
1089 | { |
1090 | struct rpc_xprt *xprt; | |
21de0a95 TM |
1091 | struct rpc_rqst *req; |
1092 | int i; | |
bd1722d4 PE |
1093 | |
1094 | xprt = kzalloc(size, GFP_KERNEL); | |
1095 | if (xprt == NULL) | |
1096 | goto out; | |
1097 | ||
21de0a95 TM |
1098 | xprt_init(xprt, net); |
1099 | ||
1100 | for (i = 0; i < num_prealloc; i++) { | |
1101 | req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); | |
1102 | if (!req) | |
8313164c | 1103 | goto out_free; |
21de0a95 TM |
1104 | list_add(&req->rq_list, &xprt->free); |
1105 | } | |
d9ba131d TM |
1106 | if (max_alloc > num_prealloc) |
1107 | xprt->max_reqs = max_alloc; | |
1108 | else | |
1109 | xprt->max_reqs = num_prealloc; | |
1110 | xprt->min_reqs = num_prealloc; | |
1111 | atomic_set(&xprt->num_reqs, num_prealloc); | |
bd1722d4 PE |
1112 | |
1113 | return xprt; | |
1114 | ||
1115 | out_free: | |
21de0a95 | 1116 | xprt_free(xprt); |
bd1722d4 PE |
1117 | out: |
1118 | return NULL; | |
1119 | } | |
1120 | EXPORT_SYMBOL_GPL(xprt_alloc); | |
1121 | ||
e204e621 PE |
1122 | void xprt_free(struct rpc_xprt *xprt) |
1123 | { | |
37aa2133 | 1124 | put_net(xprt->xprt_net); |
21de0a95 | 1125 | xprt_free_all_slots(xprt); |
e204e621 PE |
1126 | kfree(xprt); |
1127 | } | |
1128 | EXPORT_SYMBOL_GPL(xprt_free); | |
1129 | ||
9903cd1c CL |
1130 | /** |
1131 | * xprt_reserve - allocate an RPC request slot | |
1132 | * @task: RPC task requesting a slot allocation | |
1133 | * | |
ba60eb25 TM |
1134 | * If the transport is marked as being congested, or if no more |
1135 | * slots are available, place the task on the transport's | |
9903cd1c CL |
1136 | * backlog queue. |
1137 | */ | |
1138 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 | 1139 | { |
45bc0dce | 1140 | struct rpc_xprt *xprt; |
1da177e4 | 1141 | |
43cedbf0 TM |
1142 | task->tk_status = 0; |
1143 | if (task->tk_rqstp != NULL) | |
1144 | return; | |
1145 | ||
43cedbf0 TM |
1146 | task->tk_timeout = 0; |
1147 | task->tk_status = -EAGAIN; | |
45bc0dce TM |
1148 | rcu_read_lock(); |
1149 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
ba60eb25 TM |
1150 | if (!xprt_throttle_congested(xprt, task)) |
1151 | xprt->ops->alloc_slot(xprt, task); | |
1152 | rcu_read_unlock(); | |
1153 | } | |
1154 | ||
1155 | /** | |
1156 | * xprt_retry_reserve - allocate an RPC request slot | |
1157 | * @task: RPC task requesting a slot allocation | |
1158 | * | |
1159 | * If no more slots are available, place the task on the transport's | |
1160 | * backlog queue. | |
1161 | * Note that the only difference with xprt_reserve is that we now | |
1162 | * ignore the value of the XPRT_CONGESTED flag. | |
1163 | */ | |
1164 | void xprt_retry_reserve(struct rpc_task *task) | |
1165 | { | |
1166 | struct rpc_xprt *xprt; | |
1167 | ||
1168 | task->tk_status = 0; | |
1169 | if (task->tk_rqstp != NULL) | |
1170 | return; | |
1171 | ||
1172 | task->tk_timeout = 0; | |
1173 | task->tk_status = -EAGAIN; | |
1174 | rcu_read_lock(); | |
1175 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
f39c1bfb | 1176 | xprt->ops->alloc_slot(xprt, task); |
45bc0dce | 1177 | rcu_read_unlock(); |
1da177e4 LT |
1178 | } |
1179 | ||
d8ed029d | 1180 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 | 1181 | { |
0eae88f3 | 1182 | return (__force __be32)xprt->xid++; |
1da177e4 LT |
1183 | } |
1184 | ||
1185 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
1186 | { | |
63862b5b | 1187 | xprt->xid = prandom_u32(); |
1da177e4 LT |
1188 | } |
1189 | ||
9903cd1c | 1190 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
1191 | { |
1192 | struct rpc_rqst *req = task->tk_rqstp; | |
1193 | ||
d9ba131d | 1194 | INIT_LIST_HEAD(&req->rq_list); |
ba7392bb | 1195 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
1196 | req->rq_task = task; |
1197 | req->rq_xprt = xprt; | |
02107148 | 1198 | req->rq_buffer = NULL; |
1da177e4 | 1199 | req->rq_xid = xprt_alloc_xid(xprt); |
0a660521 | 1200 | req->rq_connect_cookie = xprt->connect_cookie - 1; |
92551948 TM |
1201 | req->rq_bytes_sent = 0; |
1202 | req->rq_snd_buf.len = 0; | |
1203 | req->rq_snd_buf.buflen = 0; | |
1204 | req->rq_rcv_buf.len = 0; | |
1205 | req->rq_rcv_buf.buflen = 0; | |
ead5e1c2 | 1206 | req->rq_release_snd_buf = NULL; |
da45828e | 1207 | xprt_reset_majortimeo(req); |
46121cf7 | 1208 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
1209 | req, ntohl(req->rq_xid)); |
1210 | } | |
1211 | ||
9903cd1c CL |
1212 | /** |
1213 | * xprt_release - release an RPC request slot | |
1214 | * @task: task which is finished with the slot | |
1215 | * | |
1da177e4 | 1216 | */ |
9903cd1c | 1217 | void xprt_release(struct rpc_task *task) |
1da177e4 | 1218 | { |
55ae1aab | 1219 | struct rpc_xprt *xprt; |
87ed5003 | 1220 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 | 1221 | |
87ed5003 TM |
1222 | if (req == NULL) { |
1223 | if (task->tk_client) { | |
1224 | rcu_read_lock(); | |
1225 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
1226 | if (xprt->snd_task == task) | |
1227 | xprt_release_write(xprt, task); | |
1228 | rcu_read_unlock(); | |
1229 | } | |
1da177e4 | 1230 | return; |
87ed5003 | 1231 | } |
55ae1aab | 1232 | |
55ae1aab | 1233 | xprt = req->rq_xprt; |
0a702195 WAA |
1234 | if (task->tk_ops->rpc_count_stats != NULL) |
1235 | task->tk_ops->rpc_count_stats(task, task->tk_calldata); | |
1236 | else if (task->tk_client) | |
1237 | rpc_count_iostats(task, task->tk_client->cl_metrics); | |
4a0f8c04 | 1238 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 1239 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
1240 | if (xprt->ops->release_request) |
1241 | xprt->ops->release_request(task); | |
1da177e4 LT |
1242 | if (!list_empty(&req->rq_list)) |
1243 | list_del(&req->rq_list); | |
1244 | xprt->last_used = jiffies; | |
4cfc7e60 | 1245 | if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) |
a246b010 | 1246 | mod_timer(&xprt->timer, |
03bf4b70 | 1247 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1248 | spin_unlock_bh(&xprt->transport_lock); |
ee5ebe85 | 1249 | if (req->rq_buffer) |
55ae1aab | 1250 | xprt->ops->buf_free(req->rq_buffer); |
a17c2153 TM |
1251 | if (req->rq_cred != NULL) |
1252 | put_rpccred(req->rq_cred); | |
1da177e4 | 1253 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1254 | if (req->rq_release_snd_buf) |
1255 | req->rq_release_snd_buf(req); | |
55ae1aab | 1256 | |
46121cf7 | 1257 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
ee5ebe85 TM |
1258 | if (likely(!bc_prealloc(req))) |
1259 | xprt_free_slot(xprt, req); | |
1260 | else | |
c9acb42e | 1261 | xprt_free_bc_request(req); |
1da177e4 LT |
1262 | } |
1263 | ||
21de0a95 | 1264 | static void xprt_init(struct rpc_xprt *xprt, struct net *net) |
c2866763 | 1265 | { |
21de0a95 | 1266 | atomic_set(&xprt->count, 1); |
c2866763 CL |
1267 | |
1268 | spin_lock_init(&xprt->transport_lock); | |
1269 | spin_lock_init(&xprt->reserve_lock); | |
1270 | ||
1271 | INIT_LIST_HEAD(&xprt->free); | |
1272 | INIT_LIST_HEAD(&xprt->recv); | |
9e00abc3 | 1273 | #if defined(CONFIG_SUNRPC_BACKCHANNEL) |
f9acac1a RL |
1274 | spin_lock_init(&xprt->bc_pa_lock); |
1275 | INIT_LIST_HEAD(&xprt->bc_pa_list); | |
9e00abc3 | 1276 | #endif /* CONFIG_SUNRPC_BACKCHANNEL */ |
f9acac1a | 1277 | |
c2866763 CL |
1278 | xprt->last_used = jiffies; |
1279 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1280 | xprt->bind_index = 0; |
c2866763 CL |
1281 | |
1282 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1283 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
34006cee | 1284 | rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); |
c2866763 CL |
1285 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); |
1286 | ||
c2866763 CL |
1287 | xprt_init_xid(xprt); |
1288 | ||
21de0a95 | 1289 | xprt->xprt_net = get_net(net); |
8d9266ff TM |
1290 | } |
1291 | ||
1292 | /** | |
1293 | * xprt_create_transport - create an RPC transport | |
1294 | * @args: rpc transport creation arguments | |
1295 | * | |
1296 | */ | |
1297 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) | |
1298 | { | |
1299 | struct rpc_xprt *xprt; | |
1300 | struct xprt_class *t; | |
1301 | ||
1302 | spin_lock(&xprt_list_lock); | |
1303 | list_for_each_entry(t, &xprt_list, list) { | |
1304 | if (t->ident == args->ident) { | |
1305 | spin_unlock(&xprt_list_lock); | |
1306 | goto found; | |
1307 | } | |
1308 | } | |
1309 | spin_unlock(&xprt_list_lock); | |
3c45ddf8 | 1310 | dprintk("RPC: transport (%d) not supported\n", args->ident); |
8d9266ff TM |
1311 | return ERR_PTR(-EIO); |
1312 | ||
1313 | found: | |
1314 | xprt = t->setup(args); | |
1315 | if (IS_ERR(xprt)) { | |
1316 | dprintk("RPC: xprt_create_transport: failed, %ld\n", | |
1317 | -PTR_ERR(xprt)); | |
21de0a95 | 1318 | goto out; |
8d9266ff | 1319 | } |
33d90ac0 BF |
1320 | if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) |
1321 | xprt->idle_timeout = 0; | |
21de0a95 TM |
1322 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
1323 | if (xprt_has_timer(xprt)) | |
1324 | setup_timer(&xprt->timer, xprt_init_autodisconnect, | |
1325 | (unsigned long)xprt); | |
1326 | else | |
1327 | init_timer(&xprt->timer); | |
4e0038b6 TM |
1328 | |
1329 | if (strlen(args->servername) > RPC_MAXNETNAMELEN) { | |
1330 | xprt_destroy(xprt); | |
1331 | return ERR_PTR(-EINVAL); | |
1332 | } | |
1333 | xprt->servername = kstrdup(args->servername, GFP_KERNEL); | |
1334 | if (xprt->servername == NULL) { | |
1335 | xprt_destroy(xprt); | |
1336 | return ERR_PTR(-ENOMEM); | |
1337 | } | |
1338 | ||
46121cf7 | 1339 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 | 1340 | xprt->max_reqs); |
21de0a95 | 1341 | out: |
c2866763 CL |
1342 | return xprt; |
1343 | } | |
1344 | ||
9903cd1c CL |
1345 | /** |
1346 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
a8de240a | 1347 | * @xprt: transport to destroy |
9903cd1c | 1348 | * |
1da177e4 | 1349 | */ |
a8de240a | 1350 | static void xprt_destroy(struct rpc_xprt *xprt) |
1da177e4 | 1351 | { |
46121cf7 | 1352 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 | 1353 | del_timer_sync(&xprt->timer); |
c8541ecd | 1354 | |
f6a1cc89 TM |
1355 | rpc_destroy_wait_queue(&xprt->binding); |
1356 | rpc_destroy_wait_queue(&xprt->pending); | |
1357 | rpc_destroy_wait_queue(&xprt->sending); | |
f6a1cc89 | 1358 | rpc_destroy_wait_queue(&xprt->backlog); |
c3ae62ae | 1359 | cancel_work_sync(&xprt->task_cleanup); |
4e0038b6 | 1360 | kfree(xprt->servername); |
c8541ecd CL |
1361 | /* |
1362 | * Tear down transport state and free the rpc_xprt | |
1363 | */ | |
a246b010 | 1364 | xprt->ops->destroy(xprt); |
6b6ca86b | 1365 | } |
1da177e4 | 1366 | |
6b6ca86b TM |
1367 | /** |
1368 | * xprt_put - release a reference to an RPC transport. | |
1369 | * @xprt: pointer to the transport | |
1370 | * | |
1371 | */ | |
1372 | void xprt_put(struct rpc_xprt *xprt) | |
1373 | { | |
a8de240a TM |
1374 | if (atomic_dec_and_test(&xprt->count)) |
1375 | xprt_destroy(xprt); | |
6b6ca86b | 1376 | } |