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> |
fda1bfef | 51 | #include <linux/rcupdate.h> |
1da177e4 | 52 | |
3705ad64 JL |
53 | #include <trace/events/sunrpc.h> |
54 | ||
55ae1aab RL |
55 | #include "sunrpc.h" |
56 | ||
1da177e4 LT |
57 | /* |
58 | * Local variables | |
59 | */ | |
60 | ||
f895b252 | 61 | #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) |
1da177e4 LT |
62 | # define RPCDBG_FACILITY RPCDBG_XPRT |
63 | #endif | |
64 | ||
1da177e4 LT |
65 | /* |
66 | * Local functions | |
67 | */ | |
21de0a95 | 68 | static void xprt_init(struct rpc_xprt *xprt, struct net *net); |
1da177e4 | 69 | static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); |
1da177e4 | 70 | static void xprt_connect_status(struct rpc_task *task); |
1da177e4 | 71 | static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
29807318 | 72 | static void __xprt_put_cong(struct rpc_xprt *, struct rpc_rqst *); |
4e0038b6 | 73 | static void xprt_destroy(struct rpc_xprt *xprt); |
1da177e4 | 74 | |
5ba03e82 | 75 | static DEFINE_SPINLOCK(xprt_list_lock); |
81c098af TT |
76 | static LIST_HEAD(xprt_list); |
77 | ||
81c098af TT |
78 | /** |
79 | * xprt_register_transport - register a transport implementation | |
80 | * @transport: transport to register | |
81 | * | |
82 | * If a transport implementation is loaded as a kernel module, it can | |
83 | * call this interface to make itself known to the RPC client. | |
84 | * | |
85 | * Returns: | |
86 | * 0: transport successfully registered | |
87 | * -EEXIST: transport already registered | |
88 | * -EINVAL: transport module being unloaded | |
89 | */ | |
90 | int xprt_register_transport(struct xprt_class *transport) | |
91 | { | |
92 | struct xprt_class *t; | |
93 | int result; | |
94 | ||
95 | result = -EEXIST; | |
96 | spin_lock(&xprt_list_lock); | |
97 | list_for_each_entry(t, &xprt_list, list) { | |
98 | /* don't register the same transport class twice */ | |
4fa016eb | 99 | if (t->ident == transport->ident) |
81c098af TT |
100 | goto out; |
101 | } | |
102 | ||
c9f6cde6 DL |
103 | list_add_tail(&transport->list, &xprt_list); |
104 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
105 | transport->name); | |
106 | result = 0; | |
81c098af TT |
107 | |
108 | out: | |
109 | spin_unlock(&xprt_list_lock); | |
110 | return result; | |
111 | } | |
112 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
113 | ||
114 | /** | |
115 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 116 | * @transport: transport to unregister |
81c098af TT |
117 | * |
118 | * Returns: | |
119 | * 0: transport successfully unregistered | |
120 | * -ENOENT: transport never registered | |
121 | */ | |
122 | int xprt_unregister_transport(struct xprt_class *transport) | |
123 | { | |
124 | struct xprt_class *t; | |
125 | int result; | |
126 | ||
127 | result = 0; | |
128 | spin_lock(&xprt_list_lock); | |
129 | list_for_each_entry(t, &xprt_list, list) { | |
130 | if (t == transport) { | |
131 | printk(KERN_INFO | |
132 | "RPC: Unregistered %s transport module.\n", | |
133 | transport->name); | |
134 | list_del_init(&transport->list); | |
81c098af TT |
135 | goto out; |
136 | } | |
137 | } | |
138 | result = -ENOENT; | |
139 | ||
140 | out: | |
141 | spin_unlock(&xprt_list_lock); | |
142 | return result; | |
143 | } | |
144 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
145 | ||
441e3e24 TT |
146 | /** |
147 | * xprt_load_transport - load a transport implementation | |
148 | * @transport_name: transport to load | |
149 | * | |
150 | * Returns: | |
151 | * 0: transport successfully loaded | |
152 | * -ENOENT: transport module not available | |
153 | */ | |
154 | int xprt_load_transport(const char *transport_name) | |
155 | { | |
156 | struct xprt_class *t; | |
441e3e24 TT |
157 | int result; |
158 | ||
159 | result = 0; | |
160 | spin_lock(&xprt_list_lock); | |
161 | list_for_each_entry(t, &xprt_list, list) { | |
162 | if (strcmp(t->name, transport_name) == 0) { | |
163 | spin_unlock(&xprt_list_lock); | |
164 | goto out; | |
165 | } | |
166 | } | |
167 | spin_unlock(&xprt_list_lock); | |
ef7ffe8f | 168 | result = request_module("xprt%s", transport_name); |
441e3e24 TT |
169 | out: |
170 | return result; | |
171 | } | |
172 | EXPORT_SYMBOL_GPL(xprt_load_transport); | |
173 | ||
12a80469 CL |
174 | /** |
175 | * xprt_reserve_xprt - serialize write access to transports | |
176 | * @task: task that is requesting access to the transport | |
177c27bf | 177 | * @xprt: pointer to the target transport |
12a80469 CL |
178 | * |
179 | * This prevents mixing the payload of separate requests, and prevents | |
180 | * transport connects from colliding with writes. No congestion control | |
181 | * is provided. | |
182 | */ | |
43cedbf0 | 183 | int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
12a80469 | 184 | { |
12a80469 | 185 | struct rpc_rqst *req = task->tk_rqstp; |
34006cee | 186 | int priority; |
12a80469 CL |
187 | |
188 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
189 | if (task == xprt->snd_task) | |
190 | return 1; | |
12a80469 CL |
191 | goto out_sleep; |
192 | } | |
193 | xprt->snd_task = task; | |
92551948 | 194 | if (req != NULL) |
43cedbf0 | 195 | req->rq_ntrans++; |
4d4a76f3 | 196 | |
12a80469 CL |
197 | return 1; |
198 | ||
199 | out_sleep: | |
46121cf7 | 200 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
201 | task->tk_pid, xprt); |
202 | task->tk_timeout = 0; | |
203 | task->tk_status = -EAGAIN; | |
34006cee TM |
204 | if (req == NULL) |
205 | priority = RPC_PRIORITY_LOW; | |
206 | else if (!req->rq_ntrans) | |
207 | priority = RPC_PRIORITY_NORMAL; | |
12a80469 | 208 | else |
34006cee TM |
209 | priority = RPC_PRIORITY_HIGH; |
210 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
12a80469 CL |
211 | return 0; |
212 | } | |
12444809 | 213 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 214 | |
632e3bdc TM |
215 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
216 | { | |
217 | xprt->snd_task = NULL; | |
d19751e7 | 218 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { |
4e857c58 | 219 | smp_mb__before_atomic(); |
632e3bdc | 220 | clear_bit(XPRT_LOCKED, &xprt->state); |
4e857c58 | 221 | smp_mb__after_atomic(); |
632e3bdc | 222 | } else |
40a5f1b1 | 223 | queue_work(xprtiod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
224 | } |
225 | ||
1da177e4 | 226 | /* |
12a80469 CL |
227 | * xprt_reserve_xprt_cong - serialize write access to transports |
228 | * @task: task that is requesting access to the transport | |
229 | * | |
230 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
231 | * integrated into the decision of whether a request is allowed to be | |
232 | * woken up and given access to the transport. | |
1da177e4 | 233 | */ |
43cedbf0 | 234 | int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
235 | { |
236 | struct rpc_rqst *req = task->tk_rqstp; | |
34006cee | 237 | int priority; |
1da177e4 | 238 | |
2226feb6 | 239 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
240 | if (task == xprt->snd_task) |
241 | return 1; | |
1da177e4 LT |
242 | goto out_sleep; |
243 | } | |
43cedbf0 TM |
244 | if (req == NULL) { |
245 | xprt->snd_task = task; | |
246 | return 1; | |
247 | } | |
12a80469 | 248 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 249 | xprt->snd_task = task; |
43cedbf0 | 250 | req->rq_ntrans++; |
1da177e4 LT |
251 | return 1; |
252 | } | |
632e3bdc | 253 | xprt_clear_locked(xprt); |
1da177e4 | 254 | out_sleep: |
29807318 NB |
255 | if (req) |
256 | __xprt_put_cong(xprt, req); | |
46121cf7 | 257 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
258 | task->tk_timeout = 0; |
259 | task->tk_status = -EAGAIN; | |
34006cee TM |
260 | if (req == NULL) |
261 | priority = RPC_PRIORITY_LOW; | |
262 | else if (!req->rq_ntrans) | |
263 | priority = RPC_PRIORITY_NORMAL; | |
1da177e4 | 264 | else |
34006cee TM |
265 | priority = RPC_PRIORITY_HIGH; |
266 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
1da177e4 LT |
267 | return 0; |
268 | } | |
12444809 | 269 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 270 | |
12a80469 | 271 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
272 | { |
273 | int retval; | |
274 | ||
4a0f8c04 | 275 | spin_lock_bh(&xprt->transport_lock); |
43cedbf0 | 276 | retval = xprt->ops->reserve_xprt(xprt, task); |
4a0f8c04 | 277 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
278 | return retval; |
279 | } | |
280 | ||
961a828d | 281 | static bool __xprt_lock_write_func(struct rpc_task *task, void *data) |
49e9a890 | 282 | { |
961a828d | 283 | struct rpc_xprt *xprt = data; |
49e9a890 CL |
284 | struct rpc_rqst *req; |
285 | ||
49e9a890 CL |
286 | req = task->tk_rqstp; |
287 | xprt->snd_task = task; | |
92551948 | 288 | if (req) |
49e9a890 | 289 | req->rq_ntrans++; |
961a828d TM |
290 | return true; |
291 | } | |
49e9a890 | 292 | |
961a828d TM |
293 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
294 | { | |
295 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
296 | return; | |
297 | ||
f1dc237c TM |
298 | if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, |
299 | __xprt_lock_write_func, xprt)) | |
961a828d | 300 | return; |
632e3bdc | 301 | xprt_clear_locked(xprt); |
49e9a890 CL |
302 | } |
303 | ||
961a828d | 304 | static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) |
1da177e4 | 305 | { |
961a828d | 306 | struct rpc_xprt *xprt = data; |
43cedbf0 | 307 | struct rpc_rqst *req; |
1da177e4 | 308 | |
43cedbf0 TM |
309 | req = task->tk_rqstp; |
310 | if (req == NULL) { | |
311 | xprt->snd_task = task; | |
961a828d | 312 | return true; |
43cedbf0 | 313 | } |
49e9a890 | 314 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 315 | xprt->snd_task = task; |
43cedbf0 | 316 | req->rq_ntrans++; |
961a828d | 317 | return true; |
1da177e4 | 318 | } |
961a828d TM |
319 | return false; |
320 | } | |
321 | ||
322 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
323 | { | |
324 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
325 | return; | |
326 | if (RPCXPRT_CONGESTED(xprt)) | |
327 | goto out_unlock; | |
f1dc237c TM |
328 | if (rpc_wake_up_first_on_wq(xprtiod_workqueue, &xprt->sending, |
329 | __xprt_lock_write_cong_func, xprt)) | |
961a828d | 330 | return; |
1da177e4 | 331 | out_unlock: |
632e3bdc | 332 | xprt_clear_locked(xprt); |
1da177e4 LT |
333 | } |
334 | ||
0695314e TM |
335 | static void xprt_task_clear_bytes_sent(struct rpc_task *task) |
336 | { | |
337 | if (task != NULL) { | |
338 | struct rpc_rqst *req = task->tk_rqstp; | |
339 | if (req != NULL) | |
340 | req->rq_bytes_sent = 0; | |
341 | } | |
342 | } | |
343 | ||
49e9a890 CL |
344 | /** |
345 | * xprt_release_xprt - allow other requests to use a transport | |
346 | * @xprt: transport with other tasks potentially waiting | |
347 | * @task: task that is releasing access to the transport | |
348 | * | |
349 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 350 | */ |
49e9a890 | 351 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
352 | { |
353 | if (xprt->snd_task == task) { | |
0695314e | 354 | xprt_task_clear_bytes_sent(task); |
632e3bdc | 355 | xprt_clear_locked(xprt); |
1da177e4 LT |
356 | __xprt_lock_write_next(xprt); |
357 | } | |
358 | } | |
12444809 | 359 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 360 | |
49e9a890 CL |
361 | /** |
362 | * xprt_release_xprt_cong - allow other requests to use a transport | |
363 | * @xprt: transport with other tasks potentially waiting | |
364 | * @task: task that is releasing access to the transport | |
365 | * | |
366 | * Note that "task" can be NULL. Another task is awoken to use the | |
367 | * transport if the transport's congestion window allows it. | |
368 | */ | |
369 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
370 | { | |
371 | if (xprt->snd_task == task) { | |
0695314e | 372 | xprt_task_clear_bytes_sent(task); |
632e3bdc | 373 | xprt_clear_locked(xprt); |
49e9a890 CL |
374 | __xprt_lock_write_next_cong(xprt); |
375 | } | |
376 | } | |
12444809 | 377 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
378 | |
379 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 380 | { |
4a0f8c04 | 381 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 382 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 383 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
384 | } |
385 | ||
1da177e4 LT |
386 | /* |
387 | * Van Jacobson congestion avoidance. Check if the congestion window | |
388 | * overflowed. Put the task to sleep if this is the case. | |
389 | */ | |
390 | static int | |
391 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
392 | { | |
393 | struct rpc_rqst *req = task->tk_rqstp; | |
394 | ||
395 | if (req->rq_cong) | |
396 | return 1; | |
46121cf7 | 397 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
398 | task->tk_pid, xprt->cong, xprt->cwnd); |
399 | if (RPCXPRT_CONGESTED(xprt)) | |
400 | return 0; | |
401 | req->rq_cong = 1; | |
402 | xprt->cong += RPC_CWNDSCALE; | |
403 | return 1; | |
404 | } | |
405 | ||
406 | /* | |
407 | * Adjust the congestion window, and wake up the next task | |
408 | * that has been sleeping due to congestion | |
409 | */ | |
410 | static void | |
411 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
412 | { | |
413 | if (!req->rq_cong) | |
414 | return; | |
415 | req->rq_cong = 0; | |
416 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 417 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
418 | } |
419 | ||
a58dd398 CL |
420 | /** |
421 | * xprt_release_rqst_cong - housekeeping when request is complete | |
422 | * @task: RPC request that recently completed | |
423 | * | |
424 | * Useful for transports that require congestion control. | |
425 | */ | |
426 | void xprt_release_rqst_cong(struct rpc_task *task) | |
427 | { | |
a4f0835c TM |
428 | struct rpc_rqst *req = task->tk_rqstp; |
429 | ||
430 | __xprt_put_cong(req->rq_xprt, req); | |
a58dd398 | 431 | } |
12444809 | 432 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 433 | |
46c0ee8b CL |
434 | /** |
435 | * xprt_adjust_cwnd - adjust transport congestion window | |
6a24dfb6 | 436 | * @xprt: pointer to xprt |
46c0ee8b CL |
437 | * @task: recently completed RPC request used to adjust window |
438 | * @result: result code of completed RPC request | |
439 | * | |
4f4cf5ad CL |
440 | * The transport code maintains an estimate on the maximum number of out- |
441 | * standing RPC requests, using a smoothed version of the congestion | |
442 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
443 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
444 | * halved; otherwise, it is incremented by 1/cwnd when | |
445 | * | |
446 | * - a reply is received and | |
447 | * - a full number of requests are outstanding and | |
448 | * - the congestion window hasn't been updated recently. | |
1da177e4 | 449 | */ |
6a24dfb6 | 450 | void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) |
1da177e4 | 451 | { |
46c0ee8b | 452 | struct rpc_rqst *req = task->tk_rqstp; |
46c0ee8b | 453 | unsigned long cwnd = xprt->cwnd; |
1da177e4 | 454 | |
1da177e4 LT |
455 | if (result >= 0 && cwnd <= xprt->cong) { |
456 | /* The (cwnd >> 1) term makes sure | |
457 | * the result gets rounded properly. */ | |
458 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
459 | if (cwnd > RPC_MAXCWND(xprt)) | |
460 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 461 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
462 | } else if (result == -ETIMEDOUT) { |
463 | cwnd >>= 1; | |
464 | if (cwnd < RPC_CWNDSCALE) | |
465 | cwnd = RPC_CWNDSCALE; | |
466 | } | |
46121cf7 | 467 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
468 | xprt->cong, xprt->cwnd, cwnd); |
469 | xprt->cwnd = cwnd; | |
46c0ee8b | 470 | __xprt_put_cong(xprt, req); |
1da177e4 | 471 | } |
12444809 | 472 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 473 | |
44fbac22 CL |
474 | /** |
475 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
476 | * @xprt: transport with waiting tasks | |
477 | * @status: result code to plant in each task before waking it | |
478 | * | |
479 | */ | |
480 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
481 | { | |
482 | if (status < 0) | |
483 | rpc_wake_up_status(&xprt->pending, status); | |
484 | else | |
485 | rpc_wake_up(&xprt->pending); | |
486 | } | |
12444809 | 487 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 488 | |
c7b2cae8 CL |
489 | /** |
490 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
491 | * @task: task to be put to sleep | |
0b80ae42 | 492 | * @action: function pointer to be executed after wait |
a9a6b52e TM |
493 | * |
494 | * Note that we only set the timer for the case of RPC_IS_SOFT(), since | |
495 | * we don't in general want to force a socket disconnection due to | |
496 | * an incomplete RPC call transmission. | |
c7b2cae8 | 497 | */ |
b6ddf64f | 498 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
499 | { |
500 | struct rpc_rqst *req = task->tk_rqstp; | |
501 | struct rpc_xprt *xprt = req->rq_xprt; | |
502 | ||
a9a6b52e | 503 | task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; |
b6ddf64f | 504 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 505 | } |
12444809 | 506 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
507 | |
508 | /** | |
509 | * xprt_write_space - wake the task waiting for transport output buffer space | |
510 | * @xprt: transport with waiting tasks | |
511 | * | |
512 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
513 | */ | |
514 | void xprt_write_space(struct rpc_xprt *xprt) | |
515 | { | |
c7b2cae8 CL |
516 | spin_lock_bh(&xprt->transport_lock); |
517 | if (xprt->snd_task) { | |
46121cf7 CL |
518 | dprintk("RPC: write space: waking waiting task on " |
519 | "xprt %p\n", xprt); | |
fda13939 | 520 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
521 | } |
522 | spin_unlock_bh(&xprt->transport_lock); | |
523 | } | |
12444809 | 524 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 525 | |
fe3aca29 CL |
526 | /** |
527 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
528 | * @task: task whose timeout is to be set | |
529 | * | |
530 | * Set a request's retransmit timeout based on the transport's | |
531 | * default timeout parameters. Used by transports that don't adjust | |
532 | * the retransmit timeout based on round-trip time estimation. | |
533 | */ | |
534 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
535 | { | |
536 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
537 | } | |
12444809 | 538 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 | 539 | |
2c53040f | 540 | /** |
fe3aca29 CL |
541 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout |
542 | * @task: task whose timeout is to be set | |
cca5172a | 543 | * |
fe3aca29 CL |
544 | * Set a request's retransmit timeout using the RTT estimator. |
545 | */ | |
546 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
547 | { | |
548 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
549 | struct rpc_clnt *clnt = task->tk_client; |
550 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 551 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 552 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
553 | |
554 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
555 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
556 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
557 | task->tk_timeout = max_timeout; | |
558 | } | |
12444809 | 559 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 560 | |
1da177e4 LT |
561 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
562 | { | |
ba7392bb | 563 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
564 | |
565 | req->rq_majortimeo = req->rq_timeout; | |
566 | if (to->to_exponential) | |
567 | req->rq_majortimeo <<= to->to_retries; | |
568 | else | |
569 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
570 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
571 | req->rq_majortimeo = to->to_maxval; | |
572 | req->rq_majortimeo += jiffies; | |
573 | } | |
574 | ||
9903cd1c CL |
575 | /** |
576 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
577 | * @req: RPC request containing parameters to use for the adjustment | |
578 | * | |
1da177e4 LT |
579 | */ |
580 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
581 | { | |
582 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 583 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
584 | int status = 0; |
585 | ||
586 | if (time_before(jiffies, req->rq_majortimeo)) { | |
587 | if (to->to_exponential) | |
588 | req->rq_timeout <<= 1; | |
589 | else | |
590 | req->rq_timeout += to->to_increment; | |
591 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
592 | req->rq_timeout = to->to_maxval; | |
593 | req->rq_retries++; | |
1da177e4 LT |
594 | } else { |
595 | req->rq_timeout = to->to_initval; | |
596 | req->rq_retries = 0; | |
597 | xprt_reset_majortimeo(req); | |
598 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 599 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 600 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 601 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
602 | status = -ETIMEDOUT; |
603 | } | |
604 | ||
605 | if (req->rq_timeout == 0) { | |
606 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
607 | req->rq_timeout = 5 * HZ; | |
608 | } | |
609 | return status; | |
610 | } | |
611 | ||
65f27f38 | 612 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 613 | { |
65f27f38 DH |
614 | struct rpc_xprt *xprt = |
615 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 616 | |
66af1e55 | 617 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
4876cc77 | 618 | xprt->ops->close(xprt); |
1da177e4 | 619 | xprt_release_write(xprt, NULL); |
79234c3d | 620 | wake_up_bit(&xprt->state, XPRT_LOCKED); |
1da177e4 LT |
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) | |
40a5f1b1 | 650 | queue_work(xprtiod_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) | |
40a5f1b1 | 677 | queue_work(xprtiod_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); |
40a5f1b1 | 694 | queue_work(xprtiod_workqueue, &xprt->task_cleanup); |
1da177e4 LT |
695 | return; |
696 | out_abort: | |
4a0f8c04 | 697 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
698 | } |
699 | ||
718ba5b8 TM |
700 | bool xprt_lock_connect(struct rpc_xprt *xprt, |
701 | struct rpc_task *task, | |
702 | void *cookie) | |
703 | { | |
704 | bool ret = false; | |
705 | ||
706 | spin_lock_bh(&xprt->transport_lock); | |
707 | if (!test_bit(XPRT_LOCKED, &xprt->state)) | |
708 | goto out; | |
709 | if (xprt->snd_task != task) | |
710 | goto out; | |
0695314e | 711 | xprt_task_clear_bytes_sent(task); |
718ba5b8 TM |
712 | xprt->snd_task = cookie; |
713 | ret = true; | |
714 | out: | |
715 | spin_unlock_bh(&xprt->transport_lock); | |
716 | return ret; | |
717 | } | |
718 | ||
719 | void xprt_unlock_connect(struct rpc_xprt *xprt, void *cookie) | |
720 | { | |
721 | spin_lock_bh(&xprt->transport_lock); | |
722 | if (xprt->snd_task != cookie) | |
723 | goto out; | |
724 | if (!test_bit(XPRT_LOCKED, &xprt->state)) | |
725 | goto out; | |
726 | xprt->snd_task =NULL; | |
727 | xprt->ops->release_xprt(xprt, NULL); | |
728 | out: | |
729 | spin_unlock_bh(&xprt->transport_lock); | |
79234c3d | 730 | wake_up_bit(&xprt->state, XPRT_LOCKED); |
718ba5b8 TM |
731 | } |
732 | ||
9903cd1c CL |
733 | /** |
734 | * xprt_connect - schedule a transport connect operation | |
735 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
736 | * |
737 | */ | |
738 | void xprt_connect(struct rpc_task *task) | |
739 | { | |
ad2368d6 | 740 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 741 | |
46121cf7 | 742 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
743 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
744 | ||
ec739ef0 | 745 | if (!xprt_bound(xprt)) { |
01d37c42 | 746 | task->tk_status = -EAGAIN; |
1da177e4 LT |
747 | return; |
748 | } | |
749 | if (!xprt_lock_write(xprt, task)) | |
750 | return; | |
feb8ca37 TM |
751 | |
752 | if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) | |
753 | xprt->ops->close(xprt); | |
754 | ||
718ba5b8 | 755 | if (!xprt_connected(xprt)) { |
87e3c055 | 756 | task->tk_rqstp->rq_bytes_sent = 0; |
a8ce4a8f | 757 | task->tk_timeout = task->tk_rqstp->rq_timeout; |
5d00837b | 758 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
0b9e7943 TM |
759 | |
760 | if (test_bit(XPRT_CLOSING, &xprt->state)) | |
761 | return; | |
762 | if (xprt_test_and_set_connecting(xprt)) | |
763 | return; | |
262ca07d | 764 | xprt->stat.connect_start = jiffies; |
1b092092 | 765 | xprt->ops->connect(xprt, task); |
1da177e4 | 766 | } |
718ba5b8 | 767 | xprt_release_write(xprt, task); |
1da177e4 LT |
768 | } |
769 | ||
9903cd1c | 770 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 | 771 | { |
ad2368d6 | 772 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 773 | |
cd983ef8 | 774 | if (task->tk_status == 0) { |
262ca07d CL |
775 | xprt->stat.connect_count++; |
776 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 777 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
778 | task->tk_pid); |
779 | return; | |
780 | } | |
781 | ||
1da177e4 | 782 | switch (task->tk_status) { |
0fe8d04e TM |
783 | case -ECONNREFUSED: |
784 | case -ECONNRESET: | |
785 | case -ECONNABORTED: | |
786 | case -ENETUNREACH: | |
787 | case -EHOSTUNREACH: | |
2fc193cf | 788 | case -EPIPE: |
2a491991 TM |
789 | case -EAGAIN: |
790 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 791 | break; |
1da177e4 | 792 | case -ETIMEDOUT: |
46121cf7 CL |
793 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
794 | "out\n", task->tk_pid); | |
1da177e4 LT |
795 | break; |
796 | default: | |
46121cf7 CL |
797 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
798 | "server %s\n", task->tk_pid, -task->tk_status, | |
4e0038b6 | 799 | xprt->servername); |
23475d66 | 800 | task->tk_status = -EIO; |
1da177e4 | 801 | } |
1da177e4 LT |
802 | } |
803 | ||
9903cd1c CL |
804 | /** |
805 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
806 | * @xprt: transport on which the original request was transmitted | |
807 | * @xid: RPC XID of incoming reply | |
808 | * | |
1da177e4 | 809 | */ |
d8ed029d | 810 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 | 811 | { |
8f3a6de3 | 812 | struct rpc_rqst *entry; |
1da177e4 | 813 | |
8f3a6de3 | 814 | list_for_each_entry(entry, &xprt->recv, rq_list) |
3705ad64 JL |
815 | if (entry->rq_xid == xid) { |
816 | trace_xprt_lookup_rqst(xprt, xid, 0); | |
262ca07d | 817 | return entry; |
3705ad64 | 818 | } |
46121cf7 CL |
819 | |
820 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
821 | ntohl(xid)); | |
3705ad64 | 822 | trace_xprt_lookup_rqst(xprt, xid, -ENOENT); |
262ca07d CL |
823 | xprt->stat.bad_xids++; |
824 | return NULL; | |
1da177e4 | 825 | } |
12444809 | 826 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 827 | |
bbc72cea | 828 | static void xprt_update_rtt(struct rpc_task *task) |
1570c1e4 CL |
829 | { |
830 | struct rpc_rqst *req = task->tk_rqstp; | |
831 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
95c96174 | 832 | unsigned int timer = task->tk_msg.rpc_proc->p_timer; |
d60dbb20 | 833 | long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); |
1570c1e4 CL |
834 | |
835 | if (timer) { | |
836 | if (req->rq_ntrans == 1) | |
ff839970 | 837 | rpc_update_rtt(rtt, timer, m); |
1570c1e4 CL |
838 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); |
839 | } | |
840 | } | |
841 | ||
9903cd1c CL |
842 | /** |
843 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 844 | * @task: RPC request that recently completed |
9903cd1c CL |
845 | * @copied: actual number of bytes received from the transport |
846 | * | |
1570c1e4 | 847 | * Caller holds transport lock. |
1da177e4 | 848 | */ |
1570c1e4 | 849 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 850 | { |
1570c1e4 | 851 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 852 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 853 | |
1570c1e4 CL |
854 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
855 | task->tk_pid, ntohl(req->rq_xid), copied); | |
3705ad64 | 856 | trace_xprt_complete_rqst(xprt, req->rq_xid, copied); |
1da177e4 | 857 | |
fda13939 | 858 | xprt->stat.recvs++; |
d60dbb20 | 859 | req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); |
bbc72cea CL |
860 | if (xprt->ops->timer != NULL) |
861 | xprt_update_rtt(task); | |
ef759a2e | 862 | |
1da177e4 | 863 | list_del_init(&req->rq_list); |
1e799b67 | 864 | req->rq_private_buf.len = copied; |
dd2b63d0 RL |
865 | /* Ensure all writes are done before we update */ |
866 | /* req->rq_reply_bytes_recvd */ | |
43ac3f29 | 867 | smp_wmb(); |
dd2b63d0 | 868 | req->rq_reply_bytes_recvd = copied; |
fda13939 | 869 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 870 | } |
12444809 | 871 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 872 | |
46c0ee8b | 873 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 874 | { |
46c0ee8b | 875 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
876 | struct rpc_xprt *xprt = req->rq_xprt; |
877 | ||
5d00837b TM |
878 | if (task->tk_status != -ETIMEDOUT) |
879 | return; | |
46121cf7 | 880 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 881 | |
5d00837b | 882 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 | 883 | if (!req->rq_reply_bytes_recvd) { |
46c0ee8b | 884 | if (xprt->ops->timer) |
6a24dfb6 | 885 | xprt->ops->timer(xprt, task); |
5d00837b TM |
886 | } else |
887 | task->tk_status = 0; | |
888 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
889 | } |
890 | ||
4cfc7e60 RI |
891 | static inline int xprt_has_timer(struct rpc_xprt *xprt) |
892 | { | |
893 | return xprt->idle_timeout != 0; | |
894 | } | |
895 | ||
9903cd1c CL |
896 | /** |
897 | * xprt_prepare_transmit - reserve the transport before sending a request | |
898 | * @task: RPC task about to send a request | |
899 | * | |
1da177e4 | 900 | */ |
90051ea7 | 901 | bool xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
902 | { |
903 | struct rpc_rqst *req = task->tk_rqstp; | |
904 | struct rpc_xprt *xprt = req->rq_xprt; | |
90051ea7 | 905 | bool ret = false; |
1da177e4 | 906 | |
46121cf7 | 907 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 908 | |
4a0f8c04 | 909 | spin_lock_bh(&xprt->transport_lock); |
8a19a0b6 TM |
910 | if (!req->rq_bytes_sent) { |
911 | if (req->rq_reply_bytes_recvd) { | |
912 | task->tk_status = req->rq_reply_bytes_recvd; | |
913 | goto out_unlock; | |
914 | } | |
915 | if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) | |
916 | && xprt_connected(xprt) | |
917 | && req->rq_connect_cookie == xprt->connect_cookie) { | |
918 | xprt->ops->set_retrans_timeout(task); | |
919 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
920 | goto out_unlock; | |
921 | } | |
1da177e4 | 922 | } |
90051ea7 TM |
923 | if (!xprt->ops->reserve_xprt(xprt, task)) { |
924 | task->tk_status = -EAGAIN; | |
925 | goto out_unlock; | |
926 | } | |
927 | ret = true; | |
1da177e4 | 928 | out_unlock: |
4a0f8c04 | 929 | spin_unlock_bh(&xprt->transport_lock); |
90051ea7 | 930 | return ret; |
1da177e4 LT |
931 | } |
932 | ||
e0ab53de | 933 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 934 | { |
343952fa | 935 | xprt_release_write(task->tk_rqstp->rq_xprt, task); |
5e5ce5be TM |
936 | } |
937 | ||
9903cd1c CL |
938 | /** |
939 | * xprt_transmit - send an RPC request on a transport | |
940 | * @task: controlling RPC task | |
941 | * | |
942 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
943 | */ | |
944 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 945 | { |
1da177e4 LT |
946 | struct rpc_rqst *req = task->tk_rqstp; |
947 | struct rpc_xprt *xprt = req->rq_xprt; | |
15a45206 | 948 | int status, numreqs; |
1da177e4 | 949 | |
46121cf7 | 950 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 951 | |
dd2b63d0 | 952 | if (!req->rq_reply_bytes_recvd) { |
55ae1aab RL |
953 | if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { |
954 | /* | |
955 | * Add to the list only if we're expecting a reply | |
956 | */ | |
4a0f8c04 | 957 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
958 | /* Update the softirq receive buffer */ |
959 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
960 | sizeof(req->rq_private_buf)); | |
961 | /* Add request to the receive list */ | |
962 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 963 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 964 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
965 | /* Turn off autodisconnect */ |
966 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
967 | } |
968 | } else if (!req->rq_bytes_sent) | |
969 | return; | |
970 | ||
ff839970 | 971 | req->rq_xtime = ktime_get(); |
a246b010 | 972 | status = xprt->ops->send_request(task); |
3705ad64 | 973 | trace_xprt_transmit(xprt, req->rq_xid, status); |
c8485e4d TM |
974 | if (status != 0) { |
975 | task->tk_status = status; | |
976 | return; | |
977 | } | |
4a068258 | 978 | xprt_inject_disconnect(xprt); |
262ca07d | 979 | |
c8485e4d | 980 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
468f8613 | 981 | task->tk_flags |= RPC_TASK_SENT; |
c8485e4d | 982 | spin_lock_bh(&xprt->transport_lock); |
262ca07d | 983 | |
c8485e4d | 984 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 985 | |
15a45206 AA |
986 | numreqs = atomic_read(&xprt->num_reqs); |
987 | if (numreqs > xprt->stat.max_slots) | |
988 | xprt->stat.max_slots = numreqs; | |
c8485e4d TM |
989 | xprt->stat.sends++; |
990 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
991 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
15a45206 AA |
992 | xprt->stat.sending_u += xprt->sending.qlen; |
993 | xprt->stat.pending_u += xprt->pending.qlen; | |
1da177e4 | 994 | |
c8485e4d TM |
995 | /* Don't race with disconnect */ |
996 | if (!xprt_connected(xprt)) | |
997 | task->tk_status = -ENOTCONN; | |
0a660521 | 998 | else { |
55ae1aab RL |
999 | /* |
1000 | * Sleep on the pending queue since | |
1001 | * we're expecting a reply. | |
1002 | */ | |
0a660521 TM |
1003 | if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) |
1004 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
1005 | req->rq_connect_cookie = xprt->connect_cookie; | |
55ae1aab | 1006 | } |
c8485e4d | 1007 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
1008 | } |
1009 | ||
ba60eb25 TM |
1010 | static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) |
1011 | { | |
1012 | set_bit(XPRT_CONGESTED, &xprt->state); | |
1013 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
1014 | } | |
1015 | ||
1016 | static void xprt_wake_up_backlog(struct rpc_xprt *xprt) | |
1017 | { | |
1018 | if (rpc_wake_up_next(&xprt->backlog) == NULL) | |
1019 | clear_bit(XPRT_CONGESTED, &xprt->state); | |
1020 | } | |
1021 | ||
1022 | static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) | |
1023 | { | |
1024 | bool ret = false; | |
1025 | ||
1026 | if (!test_bit(XPRT_CONGESTED, &xprt->state)) | |
1027 | goto out; | |
1028 | spin_lock(&xprt->reserve_lock); | |
1029 | if (test_bit(XPRT_CONGESTED, &xprt->state)) { | |
1030 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
1031 | ret = true; | |
1032 | } | |
1033 | spin_unlock(&xprt->reserve_lock); | |
1034 | out: | |
1035 | return ret; | |
1036 | } | |
1037 | ||
d9ba131d TM |
1038 | static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) |
1039 | { | |
1040 | struct rpc_rqst *req = ERR_PTR(-EAGAIN); | |
1041 | ||
1042 | if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) | |
1043 | goto out; | |
1044 | req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); | |
1045 | if (req != NULL) | |
1046 | goto out; | |
1047 | atomic_dec(&xprt->num_reqs); | |
1048 | req = ERR_PTR(-ENOMEM); | |
1049 | out: | |
1050 | return req; | |
1051 | } | |
1052 | ||
1053 | static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
1054 | { | |
1055 | if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { | |
1056 | kfree(req); | |
1057 | return true; | |
1058 | } | |
1059 | return false; | |
1060 | } | |
1061 | ||
f39c1bfb | 1062 | void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 | 1063 | { |
d9ba131d | 1064 | struct rpc_rqst *req; |
1da177e4 | 1065 | |
f39c1bfb | 1066 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 1067 | if (!list_empty(&xprt->free)) { |
d9ba131d TM |
1068 | req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); |
1069 | list_del(&req->rq_list); | |
1070 | goto out_init_req; | |
1071 | } | |
6b343099 | 1072 | req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN); |
d9ba131d TM |
1073 | if (!IS_ERR(req)) |
1074 | goto out_init_req; | |
1075 | switch (PTR_ERR(req)) { | |
1076 | case -ENOMEM: | |
d9ba131d TM |
1077 | dprintk("RPC: dynamic allocation of request slot " |
1078 | "failed! Retrying\n"); | |
1afeaf5c | 1079 | task->tk_status = -ENOMEM; |
d9ba131d TM |
1080 | break; |
1081 | case -EAGAIN: | |
ba60eb25 | 1082 | xprt_add_backlog(xprt, task); |
d9ba131d | 1083 | dprintk("RPC: waiting for request slot\n"); |
1afeaf5c TM |
1084 | default: |
1085 | task->tk_status = -EAGAIN; | |
1da177e4 | 1086 | } |
f39c1bfb | 1087 | spin_unlock(&xprt->reserve_lock); |
d9ba131d TM |
1088 | return; |
1089 | out_init_req: | |
1090 | task->tk_status = 0; | |
1091 | task->tk_rqstp = req; | |
1092 | xprt_request_init(task, xprt); | |
f39c1bfb TM |
1093 | spin_unlock(&xprt->reserve_lock); |
1094 | } | |
1095 | EXPORT_SYMBOL_GPL(xprt_alloc_slot); | |
1096 | ||
1097 | void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) | |
1098 | { | |
1099 | /* Note: grabbing the xprt_lock_write() ensures that we throttle | |
1100 | * new slot allocation if the transport is congested (i.e. when | |
1101 | * reconnecting a stream transport or when out of socket write | |
1102 | * buffer space). | |
1103 | */ | |
1104 | if (xprt_lock_write(xprt, task)) { | |
1105 | xprt_alloc_slot(xprt, task); | |
1106 | xprt_release_write(xprt, task); | |
1107 | } | |
1da177e4 | 1108 | } |
f39c1bfb | 1109 | EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot); |
1da177e4 | 1110 | |
ee5ebe85 TM |
1111 | static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) |
1112 | { | |
ee5ebe85 | 1113 | spin_lock(&xprt->reserve_lock); |
c25573b5 TM |
1114 | if (!xprt_dynamic_free_slot(xprt, req)) { |
1115 | memset(req, 0, sizeof(*req)); /* mark unused */ | |
1116 | list_add(&req->rq_list, &xprt->free); | |
1117 | } | |
ba60eb25 | 1118 | xprt_wake_up_backlog(xprt); |
ee5ebe85 TM |
1119 | spin_unlock(&xprt->reserve_lock); |
1120 | } | |
1121 | ||
21de0a95 TM |
1122 | static void xprt_free_all_slots(struct rpc_xprt *xprt) |
1123 | { | |
1124 | struct rpc_rqst *req; | |
1125 | while (!list_empty(&xprt->free)) { | |
1126 | req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); | |
1127 | list_del(&req->rq_list); | |
1128 | kfree(req); | |
1129 | } | |
1130 | } | |
1131 | ||
d9ba131d TM |
1132 | struct rpc_xprt *xprt_alloc(struct net *net, size_t size, |
1133 | unsigned int num_prealloc, | |
1134 | unsigned int max_alloc) | |
bd1722d4 PE |
1135 | { |
1136 | struct rpc_xprt *xprt; | |
21de0a95 TM |
1137 | struct rpc_rqst *req; |
1138 | int i; | |
bd1722d4 PE |
1139 | |
1140 | xprt = kzalloc(size, GFP_KERNEL); | |
1141 | if (xprt == NULL) | |
1142 | goto out; | |
1143 | ||
21de0a95 TM |
1144 | xprt_init(xprt, net); |
1145 | ||
1146 | for (i = 0; i < num_prealloc; i++) { | |
1147 | req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); | |
1148 | if (!req) | |
8313164c | 1149 | goto out_free; |
21de0a95 TM |
1150 | list_add(&req->rq_list, &xprt->free); |
1151 | } | |
d9ba131d TM |
1152 | if (max_alloc > num_prealloc) |
1153 | xprt->max_reqs = max_alloc; | |
1154 | else | |
1155 | xprt->max_reqs = num_prealloc; | |
1156 | xprt->min_reqs = num_prealloc; | |
1157 | atomic_set(&xprt->num_reqs, num_prealloc); | |
bd1722d4 PE |
1158 | |
1159 | return xprt; | |
1160 | ||
1161 | out_free: | |
21de0a95 | 1162 | xprt_free(xprt); |
bd1722d4 PE |
1163 | out: |
1164 | return NULL; | |
1165 | } | |
1166 | EXPORT_SYMBOL_GPL(xprt_alloc); | |
1167 | ||
e204e621 PE |
1168 | void xprt_free(struct rpc_xprt *xprt) |
1169 | { | |
37aa2133 | 1170 | put_net(xprt->xprt_net); |
21de0a95 | 1171 | xprt_free_all_slots(xprt); |
fda1bfef | 1172 | kfree_rcu(xprt, rcu); |
e204e621 PE |
1173 | } |
1174 | EXPORT_SYMBOL_GPL(xprt_free); | |
1175 | ||
9903cd1c CL |
1176 | /** |
1177 | * xprt_reserve - allocate an RPC request slot | |
1178 | * @task: RPC task requesting a slot allocation | |
1179 | * | |
ba60eb25 TM |
1180 | * If the transport is marked as being congested, or if no more |
1181 | * slots are available, place the task on the transport's | |
9903cd1c CL |
1182 | * backlog queue. |
1183 | */ | |
1184 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 | 1185 | { |
fb43d172 | 1186 | struct rpc_xprt *xprt = task->tk_xprt; |
1da177e4 | 1187 | |
43cedbf0 TM |
1188 | task->tk_status = 0; |
1189 | if (task->tk_rqstp != NULL) | |
1190 | return; | |
1191 | ||
43cedbf0 TM |
1192 | task->tk_timeout = 0; |
1193 | task->tk_status = -EAGAIN; | |
ba60eb25 TM |
1194 | if (!xprt_throttle_congested(xprt, task)) |
1195 | xprt->ops->alloc_slot(xprt, task); | |
ba60eb25 TM |
1196 | } |
1197 | ||
1198 | /** | |
1199 | * xprt_retry_reserve - allocate an RPC request slot | |
1200 | * @task: RPC task requesting a slot allocation | |
1201 | * | |
1202 | * If no more slots are available, place the task on the transport's | |
1203 | * backlog queue. | |
1204 | * Note that the only difference with xprt_reserve is that we now | |
1205 | * ignore the value of the XPRT_CONGESTED flag. | |
1206 | */ | |
1207 | void xprt_retry_reserve(struct rpc_task *task) | |
1208 | { | |
fb43d172 | 1209 | struct rpc_xprt *xprt = task->tk_xprt; |
ba60eb25 TM |
1210 | |
1211 | task->tk_status = 0; | |
1212 | if (task->tk_rqstp != NULL) | |
1213 | return; | |
1214 | ||
1215 | task->tk_timeout = 0; | |
1216 | task->tk_status = -EAGAIN; | |
f39c1bfb | 1217 | xprt->ops->alloc_slot(xprt, task); |
1da177e4 LT |
1218 | } |
1219 | ||
d8ed029d | 1220 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 | 1221 | { |
0eae88f3 | 1222 | return (__force __be32)xprt->xid++; |
1da177e4 LT |
1223 | } |
1224 | ||
1225 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
1226 | { | |
63862b5b | 1227 | xprt->xid = prandom_u32(); |
1da177e4 LT |
1228 | } |
1229 | ||
9903cd1c | 1230 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
1231 | { |
1232 | struct rpc_rqst *req = task->tk_rqstp; | |
1233 | ||
d9ba131d | 1234 | INIT_LIST_HEAD(&req->rq_list); |
ba7392bb | 1235 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
1236 | req->rq_task = task; |
1237 | req->rq_xprt = xprt; | |
02107148 | 1238 | req->rq_buffer = NULL; |
1da177e4 | 1239 | req->rq_xid = xprt_alloc_xid(xprt); |
0a660521 | 1240 | req->rq_connect_cookie = xprt->connect_cookie - 1; |
92551948 TM |
1241 | req->rq_bytes_sent = 0; |
1242 | req->rq_snd_buf.len = 0; | |
1243 | req->rq_snd_buf.buflen = 0; | |
1244 | req->rq_rcv_buf.len = 0; | |
1245 | req->rq_rcv_buf.buflen = 0; | |
ead5e1c2 | 1246 | req->rq_release_snd_buf = NULL; |
da45828e | 1247 | xprt_reset_majortimeo(req); |
46121cf7 | 1248 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
1249 | req, ntohl(req->rq_xid)); |
1250 | } | |
1251 | ||
9903cd1c CL |
1252 | /** |
1253 | * xprt_release - release an RPC request slot | |
1254 | * @task: task which is finished with the slot | |
1255 | * | |
1da177e4 | 1256 | */ |
9903cd1c | 1257 | void xprt_release(struct rpc_task *task) |
1da177e4 | 1258 | { |
55ae1aab | 1259 | struct rpc_xprt *xprt; |
87ed5003 | 1260 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 | 1261 | |
87ed5003 TM |
1262 | if (req == NULL) { |
1263 | if (task->tk_client) { | |
fb43d172 | 1264 | xprt = task->tk_xprt; |
87ed5003 TM |
1265 | if (xprt->snd_task == task) |
1266 | xprt_release_write(xprt, task); | |
87ed5003 | 1267 | } |
1da177e4 | 1268 | return; |
87ed5003 | 1269 | } |
55ae1aab | 1270 | |
55ae1aab | 1271 | xprt = req->rq_xprt; |
0a702195 WAA |
1272 | if (task->tk_ops->rpc_count_stats != NULL) |
1273 | task->tk_ops->rpc_count_stats(task, task->tk_calldata); | |
1274 | else if (task->tk_client) | |
1275 | rpc_count_iostats(task, task->tk_client->cl_metrics); | |
4a0f8c04 | 1276 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 1277 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
1278 | if (xprt->ops->release_request) |
1279 | xprt->ops->release_request(task); | |
1da177e4 LT |
1280 | if (!list_empty(&req->rq_list)) |
1281 | list_del(&req->rq_list); | |
1282 | xprt->last_used = jiffies; | |
4cfc7e60 | 1283 | if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) |
a246b010 | 1284 | mod_timer(&xprt->timer, |
03bf4b70 | 1285 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1286 | spin_unlock_bh(&xprt->transport_lock); |
ee5ebe85 | 1287 | if (req->rq_buffer) |
55ae1aab | 1288 | xprt->ops->buf_free(req->rq_buffer); |
4a068258 | 1289 | xprt_inject_disconnect(xprt); |
a17c2153 TM |
1290 | if (req->rq_cred != NULL) |
1291 | put_rpccred(req->rq_cred); | |
1da177e4 | 1292 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1293 | if (req->rq_release_snd_buf) |
1294 | req->rq_release_snd_buf(req); | |
55ae1aab | 1295 | |
46121cf7 | 1296 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
ee5ebe85 TM |
1297 | if (likely(!bc_prealloc(req))) |
1298 | xprt_free_slot(xprt, req); | |
1299 | else | |
c9acb42e | 1300 | xprt_free_bc_request(req); |
1da177e4 LT |
1301 | } |
1302 | ||
21de0a95 | 1303 | static void xprt_init(struct rpc_xprt *xprt, struct net *net) |
c2866763 | 1304 | { |
30c5116b | 1305 | kref_init(&xprt->kref); |
c2866763 CL |
1306 | |
1307 | spin_lock_init(&xprt->transport_lock); | |
1308 | spin_lock_init(&xprt->reserve_lock); | |
1309 | ||
1310 | INIT_LIST_HEAD(&xprt->free); | |
1311 | INIT_LIST_HEAD(&xprt->recv); | |
9e00abc3 | 1312 | #if defined(CONFIG_SUNRPC_BACKCHANNEL) |
f9acac1a RL |
1313 | spin_lock_init(&xprt->bc_pa_lock); |
1314 | INIT_LIST_HEAD(&xprt->bc_pa_list); | |
9e00abc3 | 1315 | #endif /* CONFIG_SUNRPC_BACKCHANNEL */ |
80b14d5e | 1316 | INIT_LIST_HEAD(&xprt->xprt_switch); |
f9acac1a | 1317 | |
c2866763 CL |
1318 | xprt->last_used = jiffies; |
1319 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1320 | xprt->bind_index = 0; |
c2866763 CL |
1321 | |
1322 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1323 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
34006cee | 1324 | rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); |
c2866763 CL |
1325 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); |
1326 | ||
c2866763 CL |
1327 | xprt_init_xid(xprt); |
1328 | ||
21de0a95 | 1329 | xprt->xprt_net = get_net(net); |
8d9266ff TM |
1330 | } |
1331 | ||
1332 | /** | |
1333 | * xprt_create_transport - create an RPC transport | |
1334 | * @args: rpc transport creation arguments | |
1335 | * | |
1336 | */ | |
1337 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) | |
1338 | { | |
1339 | struct rpc_xprt *xprt; | |
1340 | struct xprt_class *t; | |
1341 | ||
1342 | spin_lock(&xprt_list_lock); | |
1343 | list_for_each_entry(t, &xprt_list, list) { | |
1344 | if (t->ident == args->ident) { | |
1345 | spin_unlock(&xprt_list_lock); | |
1346 | goto found; | |
1347 | } | |
1348 | } | |
1349 | spin_unlock(&xprt_list_lock); | |
3c45ddf8 | 1350 | dprintk("RPC: transport (%d) not supported\n", args->ident); |
8d9266ff TM |
1351 | return ERR_PTR(-EIO); |
1352 | ||
1353 | found: | |
1354 | xprt = t->setup(args); | |
1355 | if (IS_ERR(xprt)) { | |
1356 | dprintk("RPC: xprt_create_transport: failed, %ld\n", | |
1357 | -PTR_ERR(xprt)); | |
21de0a95 | 1358 | goto out; |
8d9266ff | 1359 | } |
33d90ac0 BF |
1360 | if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) |
1361 | xprt->idle_timeout = 0; | |
21de0a95 TM |
1362 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
1363 | if (xprt_has_timer(xprt)) | |
1364 | setup_timer(&xprt->timer, xprt_init_autodisconnect, | |
1365 | (unsigned long)xprt); | |
1366 | else | |
1367 | init_timer(&xprt->timer); | |
4e0038b6 TM |
1368 | |
1369 | if (strlen(args->servername) > RPC_MAXNETNAMELEN) { | |
1370 | xprt_destroy(xprt); | |
1371 | return ERR_PTR(-EINVAL); | |
1372 | } | |
1373 | xprt->servername = kstrdup(args->servername, GFP_KERNEL); | |
1374 | if (xprt->servername == NULL) { | |
1375 | xprt_destroy(xprt); | |
1376 | return ERR_PTR(-ENOMEM); | |
1377 | } | |
1378 | ||
3f940098 | 1379 | rpc_xprt_debugfs_register(xprt); |
388f0c77 | 1380 | |
46121cf7 | 1381 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 | 1382 | xprt->max_reqs); |
21de0a95 | 1383 | out: |
c2866763 CL |
1384 | return xprt; |
1385 | } | |
1386 | ||
9903cd1c CL |
1387 | /** |
1388 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
a8de240a | 1389 | * @xprt: transport to destroy |
9903cd1c | 1390 | * |
1da177e4 | 1391 | */ |
a8de240a | 1392 | static void xprt_destroy(struct rpc_xprt *xprt) |
1da177e4 | 1393 | { |
46121cf7 | 1394 | dprintk("RPC: destroying transport %p\n", xprt); |
79234c3d TM |
1395 | |
1396 | /* Exclude transport connect/disconnect handlers */ | |
1397 | wait_on_bit_lock(&xprt->state, XPRT_LOCKED, TASK_UNINTERRUPTIBLE); | |
1398 | ||
0065db32 | 1399 | del_timer_sync(&xprt->timer); |
c8541ecd | 1400 | |
388f0c77 | 1401 | rpc_xprt_debugfs_unregister(xprt); |
f6a1cc89 TM |
1402 | rpc_destroy_wait_queue(&xprt->binding); |
1403 | rpc_destroy_wait_queue(&xprt->pending); | |
1404 | rpc_destroy_wait_queue(&xprt->sending); | |
f6a1cc89 | 1405 | rpc_destroy_wait_queue(&xprt->backlog); |
c3ae62ae | 1406 | cancel_work_sync(&xprt->task_cleanup); |
4e0038b6 | 1407 | kfree(xprt->servername); |
c8541ecd CL |
1408 | /* |
1409 | * Tear down transport state and free the rpc_xprt | |
1410 | */ | |
a246b010 | 1411 | xprt->ops->destroy(xprt); |
6b6ca86b | 1412 | } |
1da177e4 | 1413 | |
30c5116b TM |
1414 | static void xprt_destroy_kref(struct kref *kref) |
1415 | { | |
1416 | xprt_destroy(container_of(kref, struct rpc_xprt, kref)); | |
1417 | } | |
1418 | ||
1419 | /** | |
1420 | * xprt_get - return a reference to an RPC transport. | |
1421 | * @xprt: pointer to the transport | |
1422 | * | |
1423 | */ | |
1424 | struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) | |
1425 | { | |
1426 | if (xprt != NULL && kref_get_unless_zero(&xprt->kref)) | |
1427 | return xprt; | |
1428 | return NULL; | |
1429 | } | |
1430 | EXPORT_SYMBOL_GPL(xprt_get); | |
1431 | ||
6b6ca86b TM |
1432 | /** |
1433 | * xprt_put - release a reference to an RPC transport. | |
1434 | * @xprt: pointer to the transport | |
1435 | * | |
1436 | */ | |
1437 | void xprt_put(struct rpc_xprt *xprt) | |
1438 | { | |
30c5116b TM |
1439 | if (xprt != NULL) |
1440 | kref_put(&xprt->kref, xprt_destroy_kref); | |
6b6ca86b | 1441 | } |
5d252f90 | 1442 | EXPORT_SYMBOL_GPL(xprt_put); |