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 | |
3705ad64 JL |
52 | #include <trace/events/sunrpc.h> |
53 | ||
55ae1aab RL |
54 | #include "sunrpc.h" |
55 | ||
1da177e4 LT |
56 | /* |
57 | * Local variables | |
58 | */ | |
59 | ||
f895b252 | 60 | #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) |
1da177e4 LT |
61 | # define RPCDBG_FACILITY RPCDBG_XPRT |
62 | #endif | |
63 | ||
1da177e4 LT |
64 | /* |
65 | * Local functions | |
66 | */ | |
21de0a95 | 67 | static void xprt_init(struct rpc_xprt *xprt, struct net *net); |
1da177e4 | 68 | static void xprt_request_init(struct rpc_task *, struct rpc_xprt *); |
1da177e4 | 69 | static void xprt_connect_status(struct rpc_task *task); |
1da177e4 | 70 | static int __xprt_get_cong(struct rpc_xprt *, struct rpc_task *); |
4e0038b6 | 71 | static void xprt_destroy(struct rpc_xprt *xprt); |
1da177e4 | 72 | |
5ba03e82 | 73 | static DEFINE_SPINLOCK(xprt_list_lock); |
81c098af TT |
74 | static LIST_HEAD(xprt_list); |
75 | ||
81c098af TT |
76 | /** |
77 | * xprt_register_transport - register a transport implementation | |
78 | * @transport: transport to register | |
79 | * | |
80 | * If a transport implementation is loaded as a kernel module, it can | |
81 | * call this interface to make itself known to the RPC client. | |
82 | * | |
83 | * Returns: | |
84 | * 0: transport successfully registered | |
85 | * -EEXIST: transport already registered | |
86 | * -EINVAL: transport module being unloaded | |
87 | */ | |
88 | int xprt_register_transport(struct xprt_class *transport) | |
89 | { | |
90 | struct xprt_class *t; | |
91 | int result; | |
92 | ||
93 | result = -EEXIST; | |
94 | spin_lock(&xprt_list_lock); | |
95 | list_for_each_entry(t, &xprt_list, list) { | |
96 | /* don't register the same transport class twice */ | |
4fa016eb | 97 | if (t->ident == transport->ident) |
81c098af TT |
98 | goto out; |
99 | } | |
100 | ||
c9f6cde6 DL |
101 | list_add_tail(&transport->list, &xprt_list); |
102 | printk(KERN_INFO "RPC: Registered %s transport module.\n", | |
103 | transport->name); | |
104 | result = 0; | |
81c098af TT |
105 | |
106 | out: | |
107 | spin_unlock(&xprt_list_lock); | |
108 | return result; | |
109 | } | |
110 | EXPORT_SYMBOL_GPL(xprt_register_transport); | |
111 | ||
112 | /** | |
113 | * xprt_unregister_transport - unregister a transport implementation | |
65b6e42c | 114 | * @transport: transport to unregister |
81c098af TT |
115 | * |
116 | * Returns: | |
117 | * 0: transport successfully unregistered | |
118 | * -ENOENT: transport never registered | |
119 | */ | |
120 | int xprt_unregister_transport(struct xprt_class *transport) | |
121 | { | |
122 | struct xprt_class *t; | |
123 | int result; | |
124 | ||
125 | result = 0; | |
126 | spin_lock(&xprt_list_lock); | |
127 | list_for_each_entry(t, &xprt_list, list) { | |
128 | if (t == transport) { | |
129 | printk(KERN_INFO | |
130 | "RPC: Unregistered %s transport module.\n", | |
131 | transport->name); | |
132 | list_del_init(&transport->list); | |
81c098af TT |
133 | goto out; |
134 | } | |
135 | } | |
136 | result = -ENOENT; | |
137 | ||
138 | out: | |
139 | spin_unlock(&xprt_list_lock); | |
140 | return result; | |
141 | } | |
142 | EXPORT_SYMBOL_GPL(xprt_unregister_transport); | |
143 | ||
441e3e24 TT |
144 | /** |
145 | * xprt_load_transport - load a transport implementation | |
146 | * @transport_name: transport to load | |
147 | * | |
148 | * Returns: | |
149 | * 0: transport successfully loaded | |
150 | * -ENOENT: transport module not available | |
151 | */ | |
152 | int xprt_load_transport(const char *transport_name) | |
153 | { | |
154 | struct xprt_class *t; | |
441e3e24 TT |
155 | int result; |
156 | ||
157 | result = 0; | |
158 | spin_lock(&xprt_list_lock); | |
159 | list_for_each_entry(t, &xprt_list, list) { | |
160 | if (strcmp(t->name, transport_name) == 0) { | |
161 | spin_unlock(&xprt_list_lock); | |
162 | goto out; | |
163 | } | |
164 | } | |
165 | spin_unlock(&xprt_list_lock); | |
ef7ffe8f | 166 | result = request_module("xprt%s", transport_name); |
441e3e24 TT |
167 | out: |
168 | return result; | |
169 | } | |
170 | EXPORT_SYMBOL_GPL(xprt_load_transport); | |
171 | ||
12a80469 CL |
172 | /** |
173 | * xprt_reserve_xprt - serialize write access to transports | |
174 | * @task: task that is requesting access to the transport | |
177c27bf | 175 | * @xprt: pointer to the target transport |
12a80469 CL |
176 | * |
177 | * This prevents mixing the payload of separate requests, and prevents | |
178 | * transport connects from colliding with writes. No congestion control | |
179 | * is provided. | |
180 | */ | |
43cedbf0 | 181 | int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
12a80469 | 182 | { |
12a80469 | 183 | struct rpc_rqst *req = task->tk_rqstp; |
34006cee | 184 | int priority; |
12a80469 CL |
185 | |
186 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { | |
187 | if (task == xprt->snd_task) | |
188 | return 1; | |
12a80469 CL |
189 | goto out_sleep; |
190 | } | |
191 | xprt->snd_task = task; | |
92551948 | 192 | if (req != NULL) |
43cedbf0 | 193 | req->rq_ntrans++; |
4d4a76f3 | 194 | |
12a80469 CL |
195 | return 1; |
196 | ||
197 | out_sleep: | |
46121cf7 | 198 | dprintk("RPC: %5u failed to lock transport %p\n", |
12a80469 CL |
199 | task->tk_pid, xprt); |
200 | task->tk_timeout = 0; | |
201 | task->tk_status = -EAGAIN; | |
34006cee TM |
202 | if (req == NULL) |
203 | priority = RPC_PRIORITY_LOW; | |
204 | else if (!req->rq_ntrans) | |
205 | priority = RPC_PRIORITY_NORMAL; | |
12a80469 | 206 | else |
34006cee TM |
207 | priority = RPC_PRIORITY_HIGH; |
208 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
12a80469 CL |
209 | return 0; |
210 | } | |
12444809 | 211 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt); |
12a80469 | 212 | |
632e3bdc TM |
213 | static void xprt_clear_locked(struct rpc_xprt *xprt) |
214 | { | |
215 | xprt->snd_task = NULL; | |
d19751e7 | 216 | if (!test_bit(XPRT_CLOSE_WAIT, &xprt->state)) { |
4e857c58 | 217 | smp_mb__before_atomic(); |
632e3bdc | 218 | clear_bit(XPRT_LOCKED, &xprt->state); |
4e857c58 | 219 | smp_mb__after_atomic(); |
632e3bdc | 220 | } else |
c1384c9c | 221 | queue_work(rpciod_workqueue, &xprt->task_cleanup); |
632e3bdc TM |
222 | } |
223 | ||
1da177e4 | 224 | /* |
12a80469 CL |
225 | * xprt_reserve_xprt_cong - serialize write access to transports |
226 | * @task: task that is requesting access to the transport | |
227 | * | |
228 | * Same as xprt_reserve_xprt, but Van Jacobson congestion control is | |
229 | * integrated into the decision of whether a request is allowed to be | |
230 | * woken up and given access to the transport. | |
1da177e4 | 231 | */ |
43cedbf0 | 232 | int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
233 | { |
234 | struct rpc_rqst *req = task->tk_rqstp; | |
34006cee | 235 | int priority; |
1da177e4 | 236 | |
2226feb6 | 237 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) { |
1da177e4 LT |
238 | if (task == xprt->snd_task) |
239 | return 1; | |
1da177e4 LT |
240 | goto out_sleep; |
241 | } | |
43cedbf0 TM |
242 | if (req == NULL) { |
243 | xprt->snd_task = task; | |
244 | return 1; | |
245 | } | |
12a80469 | 246 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 247 | xprt->snd_task = task; |
43cedbf0 | 248 | req->rq_ntrans++; |
1da177e4 LT |
249 | return 1; |
250 | } | |
632e3bdc | 251 | xprt_clear_locked(xprt); |
1da177e4 | 252 | out_sleep: |
46121cf7 | 253 | dprintk("RPC: %5u failed to lock transport %p\n", task->tk_pid, xprt); |
1da177e4 LT |
254 | task->tk_timeout = 0; |
255 | task->tk_status = -EAGAIN; | |
34006cee TM |
256 | if (req == NULL) |
257 | priority = RPC_PRIORITY_LOW; | |
258 | else if (!req->rq_ntrans) | |
259 | priority = RPC_PRIORITY_NORMAL; | |
1da177e4 | 260 | else |
34006cee TM |
261 | priority = RPC_PRIORITY_HIGH; |
262 | rpc_sleep_on_priority(&xprt->sending, task, NULL, priority); | |
1da177e4 LT |
263 | return 0; |
264 | } | |
12444809 | 265 | EXPORT_SYMBOL_GPL(xprt_reserve_xprt_cong); |
1da177e4 | 266 | |
12a80469 | 267 | static inline int xprt_lock_write(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
268 | { |
269 | int retval; | |
270 | ||
4a0f8c04 | 271 | spin_lock_bh(&xprt->transport_lock); |
43cedbf0 | 272 | retval = xprt->ops->reserve_xprt(xprt, task); |
4a0f8c04 | 273 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
274 | return retval; |
275 | } | |
276 | ||
961a828d | 277 | static bool __xprt_lock_write_func(struct rpc_task *task, void *data) |
49e9a890 | 278 | { |
961a828d | 279 | struct rpc_xprt *xprt = data; |
49e9a890 CL |
280 | struct rpc_rqst *req; |
281 | ||
49e9a890 CL |
282 | req = task->tk_rqstp; |
283 | xprt->snd_task = task; | |
92551948 | 284 | if (req) |
49e9a890 | 285 | req->rq_ntrans++; |
961a828d TM |
286 | return true; |
287 | } | |
49e9a890 | 288 | |
961a828d TM |
289 | static void __xprt_lock_write_next(struct rpc_xprt *xprt) |
290 | { | |
291 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
292 | return; | |
293 | ||
294 | if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_func, xprt)) | |
295 | return; | |
632e3bdc | 296 | xprt_clear_locked(xprt); |
49e9a890 CL |
297 | } |
298 | ||
961a828d | 299 | static bool __xprt_lock_write_cong_func(struct rpc_task *task, void *data) |
1da177e4 | 300 | { |
961a828d | 301 | struct rpc_xprt *xprt = data; |
43cedbf0 | 302 | struct rpc_rqst *req; |
1da177e4 | 303 | |
43cedbf0 TM |
304 | req = task->tk_rqstp; |
305 | if (req == NULL) { | |
306 | xprt->snd_task = task; | |
961a828d | 307 | return true; |
43cedbf0 | 308 | } |
49e9a890 | 309 | if (__xprt_get_cong(xprt, task)) { |
1da177e4 | 310 | xprt->snd_task = task; |
43cedbf0 | 311 | req->rq_ntrans++; |
961a828d | 312 | return true; |
1da177e4 | 313 | } |
961a828d TM |
314 | return false; |
315 | } | |
316 | ||
317 | static void __xprt_lock_write_next_cong(struct rpc_xprt *xprt) | |
318 | { | |
319 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) | |
320 | return; | |
321 | if (RPCXPRT_CONGESTED(xprt)) | |
322 | goto out_unlock; | |
323 | if (rpc_wake_up_first(&xprt->sending, __xprt_lock_write_cong_func, xprt)) | |
324 | return; | |
1da177e4 | 325 | out_unlock: |
632e3bdc | 326 | xprt_clear_locked(xprt); |
1da177e4 LT |
327 | } |
328 | ||
49e9a890 CL |
329 | /** |
330 | * xprt_release_xprt - allow other requests to use a transport | |
331 | * @xprt: transport with other tasks potentially waiting | |
332 | * @task: task that is releasing access to the transport | |
333 | * | |
334 | * Note that "task" can be NULL. No congestion control is provided. | |
1da177e4 | 335 | */ |
49e9a890 | 336 | void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 LT |
337 | { |
338 | if (xprt->snd_task == task) { | |
ee071eff TM |
339 | if (task != NULL) { |
340 | struct rpc_rqst *req = task->tk_rqstp; | |
341 | if (req != NULL) | |
342 | req->rq_bytes_sent = 0; | |
343 | } | |
632e3bdc | 344 | xprt_clear_locked(xprt); |
1da177e4 LT |
345 | __xprt_lock_write_next(xprt); |
346 | } | |
347 | } | |
12444809 | 348 | EXPORT_SYMBOL_GPL(xprt_release_xprt); |
1da177e4 | 349 | |
49e9a890 CL |
350 | /** |
351 | * xprt_release_xprt_cong - allow other requests to use a transport | |
352 | * @xprt: transport with other tasks potentially waiting | |
353 | * @task: task that is releasing access to the transport | |
354 | * | |
355 | * Note that "task" can be NULL. Another task is awoken to use the | |
356 | * transport if the transport's congestion window allows it. | |
357 | */ | |
358 | void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
359 | { | |
360 | if (xprt->snd_task == task) { | |
ee071eff TM |
361 | if (task != NULL) { |
362 | struct rpc_rqst *req = task->tk_rqstp; | |
363 | if (req != NULL) | |
364 | req->rq_bytes_sent = 0; | |
365 | } | |
632e3bdc | 366 | xprt_clear_locked(xprt); |
49e9a890 CL |
367 | __xprt_lock_write_next_cong(xprt); |
368 | } | |
369 | } | |
12444809 | 370 | EXPORT_SYMBOL_GPL(xprt_release_xprt_cong); |
49e9a890 CL |
371 | |
372 | static inline void xprt_release_write(struct rpc_xprt *xprt, struct rpc_task *task) | |
1da177e4 | 373 | { |
4a0f8c04 | 374 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 375 | xprt->ops->release_xprt(xprt, task); |
4a0f8c04 | 376 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
377 | } |
378 | ||
1da177e4 LT |
379 | /* |
380 | * Van Jacobson congestion avoidance. Check if the congestion window | |
381 | * overflowed. Put the task to sleep if this is the case. | |
382 | */ | |
383 | static int | |
384 | __xprt_get_cong(struct rpc_xprt *xprt, struct rpc_task *task) | |
385 | { | |
386 | struct rpc_rqst *req = task->tk_rqstp; | |
387 | ||
388 | if (req->rq_cong) | |
389 | return 1; | |
46121cf7 | 390 | dprintk("RPC: %5u xprt_cwnd_limited cong = %lu cwnd = %lu\n", |
1da177e4 LT |
391 | task->tk_pid, xprt->cong, xprt->cwnd); |
392 | if (RPCXPRT_CONGESTED(xprt)) | |
393 | return 0; | |
394 | req->rq_cong = 1; | |
395 | xprt->cong += RPC_CWNDSCALE; | |
396 | return 1; | |
397 | } | |
398 | ||
399 | /* | |
400 | * Adjust the congestion window, and wake up the next task | |
401 | * that has been sleeping due to congestion | |
402 | */ | |
403 | static void | |
404 | __xprt_put_cong(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
405 | { | |
406 | if (!req->rq_cong) | |
407 | return; | |
408 | req->rq_cong = 0; | |
409 | xprt->cong -= RPC_CWNDSCALE; | |
49e9a890 | 410 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
411 | } |
412 | ||
a58dd398 CL |
413 | /** |
414 | * xprt_release_rqst_cong - housekeeping when request is complete | |
415 | * @task: RPC request that recently completed | |
416 | * | |
417 | * Useful for transports that require congestion control. | |
418 | */ | |
419 | void xprt_release_rqst_cong(struct rpc_task *task) | |
420 | { | |
a4f0835c TM |
421 | struct rpc_rqst *req = task->tk_rqstp; |
422 | ||
423 | __xprt_put_cong(req->rq_xprt, req); | |
a58dd398 | 424 | } |
12444809 | 425 | EXPORT_SYMBOL_GPL(xprt_release_rqst_cong); |
a58dd398 | 426 | |
46c0ee8b CL |
427 | /** |
428 | * xprt_adjust_cwnd - adjust transport congestion window | |
6a24dfb6 | 429 | * @xprt: pointer to xprt |
46c0ee8b CL |
430 | * @task: recently completed RPC request used to adjust window |
431 | * @result: result code of completed RPC request | |
432 | * | |
4f4cf5ad CL |
433 | * The transport code maintains an estimate on the maximum number of out- |
434 | * standing RPC requests, using a smoothed version of the congestion | |
435 | * avoidance implemented in 44BSD. This is basically the Van Jacobson | |
436 | * congestion algorithm: If a retransmit occurs, the congestion window is | |
437 | * halved; otherwise, it is incremented by 1/cwnd when | |
438 | * | |
439 | * - a reply is received and | |
440 | * - a full number of requests are outstanding and | |
441 | * - the congestion window hasn't been updated recently. | |
1da177e4 | 442 | */ |
6a24dfb6 | 443 | void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result) |
1da177e4 | 444 | { |
46c0ee8b | 445 | struct rpc_rqst *req = task->tk_rqstp; |
46c0ee8b | 446 | unsigned long cwnd = xprt->cwnd; |
1da177e4 | 447 | |
1da177e4 LT |
448 | if (result >= 0 && cwnd <= xprt->cong) { |
449 | /* The (cwnd >> 1) term makes sure | |
450 | * the result gets rounded properly. */ | |
451 | cwnd += (RPC_CWNDSCALE * RPC_CWNDSCALE + (cwnd >> 1)) / cwnd; | |
452 | if (cwnd > RPC_MAXCWND(xprt)) | |
453 | cwnd = RPC_MAXCWND(xprt); | |
49e9a890 | 454 | __xprt_lock_write_next_cong(xprt); |
1da177e4 LT |
455 | } else if (result == -ETIMEDOUT) { |
456 | cwnd >>= 1; | |
457 | if (cwnd < RPC_CWNDSCALE) | |
458 | cwnd = RPC_CWNDSCALE; | |
459 | } | |
46121cf7 | 460 | dprintk("RPC: cong %ld, cwnd was %ld, now %ld\n", |
1da177e4 LT |
461 | xprt->cong, xprt->cwnd, cwnd); |
462 | xprt->cwnd = cwnd; | |
46c0ee8b | 463 | __xprt_put_cong(xprt, req); |
1da177e4 | 464 | } |
12444809 | 465 | EXPORT_SYMBOL_GPL(xprt_adjust_cwnd); |
1da177e4 | 466 | |
44fbac22 CL |
467 | /** |
468 | * xprt_wake_pending_tasks - wake all tasks on a transport's pending queue | |
469 | * @xprt: transport with waiting tasks | |
470 | * @status: result code to plant in each task before waking it | |
471 | * | |
472 | */ | |
473 | void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status) | |
474 | { | |
475 | if (status < 0) | |
476 | rpc_wake_up_status(&xprt->pending, status); | |
477 | else | |
478 | rpc_wake_up(&xprt->pending); | |
479 | } | |
12444809 | 480 | EXPORT_SYMBOL_GPL(xprt_wake_pending_tasks); |
44fbac22 | 481 | |
c7b2cae8 CL |
482 | /** |
483 | * xprt_wait_for_buffer_space - wait for transport output buffer to clear | |
484 | * @task: task to be put to sleep | |
0b80ae42 | 485 | * @action: function pointer to be executed after wait |
a9a6b52e TM |
486 | * |
487 | * Note that we only set the timer for the case of RPC_IS_SOFT(), since | |
488 | * we don't in general want to force a socket disconnection due to | |
489 | * an incomplete RPC call transmission. | |
c7b2cae8 | 490 | */ |
b6ddf64f | 491 | void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action) |
c7b2cae8 CL |
492 | { |
493 | struct rpc_rqst *req = task->tk_rqstp; | |
494 | struct rpc_xprt *xprt = req->rq_xprt; | |
495 | ||
a9a6b52e | 496 | task->tk_timeout = RPC_IS_SOFT(task) ? req->rq_timeout : 0; |
b6ddf64f | 497 | rpc_sleep_on(&xprt->pending, task, action); |
c7b2cae8 | 498 | } |
12444809 | 499 | EXPORT_SYMBOL_GPL(xprt_wait_for_buffer_space); |
c7b2cae8 CL |
500 | |
501 | /** | |
502 | * xprt_write_space - wake the task waiting for transport output buffer space | |
503 | * @xprt: transport with waiting tasks | |
504 | * | |
505 | * Can be called in a soft IRQ context, so xprt_write_space never sleeps. | |
506 | */ | |
507 | void xprt_write_space(struct rpc_xprt *xprt) | |
508 | { | |
c7b2cae8 CL |
509 | spin_lock_bh(&xprt->transport_lock); |
510 | if (xprt->snd_task) { | |
46121cf7 CL |
511 | dprintk("RPC: write space: waking waiting task on " |
512 | "xprt %p\n", xprt); | |
fda13939 | 513 | rpc_wake_up_queued_task(&xprt->pending, xprt->snd_task); |
c7b2cae8 CL |
514 | } |
515 | spin_unlock_bh(&xprt->transport_lock); | |
516 | } | |
12444809 | 517 | EXPORT_SYMBOL_GPL(xprt_write_space); |
c7b2cae8 | 518 | |
fe3aca29 CL |
519 | /** |
520 | * xprt_set_retrans_timeout_def - set a request's retransmit timeout | |
521 | * @task: task whose timeout is to be set | |
522 | * | |
523 | * Set a request's retransmit timeout based on the transport's | |
524 | * default timeout parameters. Used by transports that don't adjust | |
525 | * the retransmit timeout based on round-trip time estimation. | |
526 | */ | |
527 | void xprt_set_retrans_timeout_def(struct rpc_task *task) | |
528 | { | |
529 | task->tk_timeout = task->tk_rqstp->rq_timeout; | |
530 | } | |
12444809 | 531 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_def); |
fe3aca29 | 532 | |
2c53040f | 533 | /** |
fe3aca29 CL |
534 | * xprt_set_retrans_timeout_rtt - set a request's retransmit timeout |
535 | * @task: task whose timeout is to be set | |
cca5172a | 536 | * |
fe3aca29 CL |
537 | * Set a request's retransmit timeout using the RTT estimator. |
538 | */ | |
539 | void xprt_set_retrans_timeout_rtt(struct rpc_task *task) | |
540 | { | |
541 | int timer = task->tk_msg.rpc_proc->p_timer; | |
ba7392bb TM |
542 | struct rpc_clnt *clnt = task->tk_client; |
543 | struct rpc_rtt *rtt = clnt->cl_rtt; | |
fe3aca29 | 544 | struct rpc_rqst *req = task->tk_rqstp; |
ba7392bb | 545 | unsigned long max_timeout = clnt->cl_timeout->to_maxval; |
fe3aca29 CL |
546 | |
547 | task->tk_timeout = rpc_calc_rto(rtt, timer); | |
548 | task->tk_timeout <<= rpc_ntimeo(rtt, timer) + req->rq_retries; | |
549 | if (task->tk_timeout > max_timeout || task->tk_timeout == 0) | |
550 | task->tk_timeout = max_timeout; | |
551 | } | |
12444809 | 552 | EXPORT_SYMBOL_GPL(xprt_set_retrans_timeout_rtt); |
fe3aca29 | 553 | |
1da177e4 LT |
554 | static void xprt_reset_majortimeo(struct rpc_rqst *req) |
555 | { | |
ba7392bb | 556 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
557 | |
558 | req->rq_majortimeo = req->rq_timeout; | |
559 | if (to->to_exponential) | |
560 | req->rq_majortimeo <<= to->to_retries; | |
561 | else | |
562 | req->rq_majortimeo += to->to_increment * to->to_retries; | |
563 | if (req->rq_majortimeo > to->to_maxval || req->rq_majortimeo == 0) | |
564 | req->rq_majortimeo = to->to_maxval; | |
565 | req->rq_majortimeo += jiffies; | |
566 | } | |
567 | ||
9903cd1c CL |
568 | /** |
569 | * xprt_adjust_timeout - adjust timeout values for next retransmit | |
570 | * @req: RPC request containing parameters to use for the adjustment | |
571 | * | |
1da177e4 LT |
572 | */ |
573 | int xprt_adjust_timeout(struct rpc_rqst *req) | |
574 | { | |
575 | struct rpc_xprt *xprt = req->rq_xprt; | |
ba7392bb | 576 | const struct rpc_timeout *to = req->rq_task->tk_client->cl_timeout; |
1da177e4 LT |
577 | int status = 0; |
578 | ||
579 | if (time_before(jiffies, req->rq_majortimeo)) { | |
580 | if (to->to_exponential) | |
581 | req->rq_timeout <<= 1; | |
582 | else | |
583 | req->rq_timeout += to->to_increment; | |
584 | if (to->to_maxval && req->rq_timeout >= to->to_maxval) | |
585 | req->rq_timeout = to->to_maxval; | |
586 | req->rq_retries++; | |
1da177e4 LT |
587 | } else { |
588 | req->rq_timeout = to->to_initval; | |
589 | req->rq_retries = 0; | |
590 | xprt_reset_majortimeo(req); | |
591 | /* Reset the RTT counters == "slow start" */ | |
4a0f8c04 | 592 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 593 | rpc_init_rtt(req->rq_task->tk_client->cl_rtt, to->to_initval); |
4a0f8c04 | 594 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
595 | status = -ETIMEDOUT; |
596 | } | |
597 | ||
598 | if (req->rq_timeout == 0) { | |
599 | printk(KERN_WARNING "xprt_adjust_timeout: rq_timeout = 0!\n"); | |
600 | req->rq_timeout = 5 * HZ; | |
601 | } | |
602 | return status; | |
603 | } | |
604 | ||
65f27f38 | 605 | static void xprt_autoclose(struct work_struct *work) |
1da177e4 | 606 | { |
65f27f38 DH |
607 | struct rpc_xprt *xprt = |
608 | container_of(work, struct rpc_xprt, task_cleanup); | |
1da177e4 | 609 | |
a246b010 | 610 | xprt->ops->close(xprt); |
66af1e55 | 611 | clear_bit(XPRT_CLOSE_WAIT, &xprt->state); |
1da177e4 LT |
612 | xprt_release_write(xprt, NULL); |
613 | } | |
614 | ||
9903cd1c | 615 | /** |
62da3b24 | 616 | * xprt_disconnect_done - mark a transport as disconnected |
9903cd1c CL |
617 | * @xprt: transport to flag for disconnect |
618 | * | |
1da177e4 | 619 | */ |
62da3b24 | 620 | void xprt_disconnect_done(struct rpc_xprt *xprt) |
1da177e4 | 621 | { |
46121cf7 | 622 | dprintk("RPC: disconnected transport %p\n", xprt); |
4a0f8c04 | 623 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 | 624 | xprt_clear_connected(xprt); |
2a491991 | 625 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
4a0f8c04 | 626 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 627 | } |
62da3b24 | 628 | EXPORT_SYMBOL_GPL(xprt_disconnect_done); |
1da177e4 | 629 | |
66af1e55 TM |
630 | /** |
631 | * xprt_force_disconnect - force a transport to disconnect | |
632 | * @xprt: transport to disconnect | |
633 | * | |
634 | */ | |
635 | void xprt_force_disconnect(struct rpc_xprt *xprt) | |
636 | { | |
637 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
638 | spin_lock_bh(&xprt->transport_lock); | |
639 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
640 | /* Try to schedule an autoclose RPC call */ | |
641 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
642 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 643 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
66af1e55 TM |
644 | spin_unlock_bh(&xprt->transport_lock); |
645 | } | |
66af1e55 | 646 | |
7c1d71cf TM |
647 | /** |
648 | * xprt_conditional_disconnect - force a transport to disconnect | |
649 | * @xprt: transport to disconnect | |
650 | * @cookie: 'connection cookie' | |
651 | * | |
652 | * This attempts to break the connection if and only if 'cookie' matches | |
653 | * the current transport 'connection cookie'. It ensures that we don't | |
654 | * try to break the connection more than once when we need to retransmit | |
655 | * a batch of RPC requests. | |
656 | * | |
657 | */ | |
658 | void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie) | |
659 | { | |
660 | /* Don't race with the test_bit() in xprt_clear_locked() */ | |
661 | spin_lock_bh(&xprt->transport_lock); | |
662 | if (cookie != xprt->connect_cookie) | |
663 | goto out; | |
664 | if (test_bit(XPRT_CLOSING, &xprt->state) || !xprt_connected(xprt)) | |
665 | goto out; | |
666 | set_bit(XPRT_CLOSE_WAIT, &xprt->state); | |
667 | /* Try to schedule an autoclose RPC call */ | |
668 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state) == 0) | |
669 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
2a491991 | 670 | xprt_wake_pending_tasks(xprt, -EAGAIN); |
7c1d71cf TM |
671 | out: |
672 | spin_unlock_bh(&xprt->transport_lock); | |
673 | } | |
674 | ||
1da177e4 LT |
675 | static void |
676 | xprt_init_autodisconnect(unsigned long data) | |
677 | { | |
678 | struct rpc_xprt *xprt = (struct rpc_xprt *)data; | |
679 | ||
4a0f8c04 | 680 | spin_lock(&xprt->transport_lock); |
d19751e7 | 681 | if (!list_empty(&xprt->recv)) |
1da177e4 | 682 | goto out_abort; |
2226feb6 | 683 | if (test_and_set_bit(XPRT_LOCKED, &xprt->state)) |
1da177e4 | 684 | goto out_abort; |
4a0f8c04 | 685 | spin_unlock(&xprt->transport_lock); |
f75e6745 TM |
686 | set_bit(XPRT_CONNECTION_CLOSE, &xprt->state); |
687 | queue_work(rpciod_workqueue, &xprt->task_cleanup); | |
1da177e4 LT |
688 | return; |
689 | out_abort: | |
4a0f8c04 | 690 | spin_unlock(&xprt->transport_lock); |
1da177e4 LT |
691 | } |
692 | ||
9903cd1c CL |
693 | /** |
694 | * xprt_connect - schedule a transport connect operation | |
695 | * @task: RPC task that is requesting the connect | |
1da177e4 LT |
696 | * |
697 | */ | |
698 | void xprt_connect(struct rpc_task *task) | |
699 | { | |
ad2368d6 | 700 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 701 | |
46121cf7 | 702 | dprintk("RPC: %5u xprt_connect xprt %p %s connected\n", task->tk_pid, |
1da177e4 LT |
703 | xprt, (xprt_connected(xprt) ? "is" : "is not")); |
704 | ||
ec739ef0 | 705 | if (!xprt_bound(xprt)) { |
01d37c42 | 706 | task->tk_status = -EAGAIN; |
1da177e4 LT |
707 | return; |
708 | } | |
709 | if (!xprt_lock_write(xprt, task)) | |
710 | return; | |
feb8ca37 TM |
711 | |
712 | if (test_and_clear_bit(XPRT_CLOSE_WAIT, &xprt->state)) | |
713 | xprt->ops->close(xprt); | |
714 | ||
1da177e4 | 715 | if (xprt_connected(xprt)) |
a246b010 CL |
716 | xprt_release_write(xprt, task); |
717 | else { | |
87e3c055 | 718 | task->tk_rqstp->rq_bytes_sent = 0; |
a8ce4a8f | 719 | task->tk_timeout = task->tk_rqstp->rq_timeout; |
5d00837b | 720 | rpc_sleep_on(&xprt->pending, task, xprt_connect_status); |
0b9e7943 TM |
721 | |
722 | if (test_bit(XPRT_CLOSING, &xprt->state)) | |
723 | return; | |
724 | if (xprt_test_and_set_connecting(xprt)) | |
725 | return; | |
262ca07d | 726 | xprt->stat.connect_start = jiffies; |
1b092092 | 727 | xprt->ops->connect(xprt, task); |
1da177e4 | 728 | } |
1da177e4 LT |
729 | } |
730 | ||
9903cd1c | 731 | static void xprt_connect_status(struct rpc_task *task) |
1da177e4 | 732 | { |
ad2368d6 | 733 | struct rpc_xprt *xprt = task->tk_rqstp->rq_xprt; |
1da177e4 | 734 | |
cd983ef8 | 735 | if (task->tk_status == 0) { |
262ca07d CL |
736 | xprt->stat.connect_count++; |
737 | xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start; | |
46121cf7 | 738 | dprintk("RPC: %5u xprt_connect_status: connection established\n", |
1da177e4 LT |
739 | task->tk_pid); |
740 | return; | |
741 | } | |
742 | ||
1da177e4 | 743 | switch (task->tk_status) { |
0fe8d04e TM |
744 | case -ECONNREFUSED: |
745 | case -ECONNRESET: | |
746 | case -ECONNABORTED: | |
747 | case -ENETUNREACH: | |
748 | case -EHOSTUNREACH: | |
2fc193cf | 749 | case -EPIPE: |
2a491991 TM |
750 | case -EAGAIN: |
751 | dprintk("RPC: %5u xprt_connect_status: retrying\n", task->tk_pid); | |
23475d66 | 752 | break; |
1da177e4 | 753 | case -ETIMEDOUT: |
46121cf7 CL |
754 | dprintk("RPC: %5u xprt_connect_status: connect attempt timed " |
755 | "out\n", task->tk_pid); | |
1da177e4 LT |
756 | break; |
757 | default: | |
46121cf7 CL |
758 | dprintk("RPC: %5u xprt_connect_status: error %d connecting to " |
759 | "server %s\n", task->tk_pid, -task->tk_status, | |
4e0038b6 | 760 | xprt->servername); |
23475d66 CL |
761 | xprt_release_write(xprt, task); |
762 | task->tk_status = -EIO; | |
1da177e4 | 763 | } |
1da177e4 LT |
764 | } |
765 | ||
9903cd1c CL |
766 | /** |
767 | * xprt_lookup_rqst - find an RPC request corresponding to an XID | |
768 | * @xprt: transport on which the original request was transmitted | |
769 | * @xid: RPC XID of incoming reply | |
770 | * | |
1da177e4 | 771 | */ |
d8ed029d | 772 | struct rpc_rqst *xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid) |
1da177e4 | 773 | { |
8f3a6de3 | 774 | struct rpc_rqst *entry; |
1da177e4 | 775 | |
8f3a6de3 | 776 | list_for_each_entry(entry, &xprt->recv, rq_list) |
3705ad64 JL |
777 | if (entry->rq_xid == xid) { |
778 | trace_xprt_lookup_rqst(xprt, xid, 0); | |
262ca07d | 779 | return entry; |
3705ad64 | 780 | } |
46121cf7 CL |
781 | |
782 | dprintk("RPC: xprt_lookup_rqst did not find xid %08x\n", | |
783 | ntohl(xid)); | |
3705ad64 | 784 | trace_xprt_lookup_rqst(xprt, xid, -ENOENT); |
262ca07d CL |
785 | xprt->stat.bad_xids++; |
786 | return NULL; | |
1da177e4 | 787 | } |
12444809 | 788 | EXPORT_SYMBOL_GPL(xprt_lookup_rqst); |
1da177e4 | 789 | |
bbc72cea | 790 | static void xprt_update_rtt(struct rpc_task *task) |
1570c1e4 CL |
791 | { |
792 | struct rpc_rqst *req = task->tk_rqstp; | |
793 | struct rpc_rtt *rtt = task->tk_client->cl_rtt; | |
95c96174 | 794 | unsigned int timer = task->tk_msg.rpc_proc->p_timer; |
d60dbb20 | 795 | long m = usecs_to_jiffies(ktime_to_us(req->rq_rtt)); |
1570c1e4 CL |
796 | |
797 | if (timer) { | |
798 | if (req->rq_ntrans == 1) | |
ff839970 | 799 | rpc_update_rtt(rtt, timer, m); |
1570c1e4 CL |
800 | rpc_set_timeo(rtt, timer, req->rq_ntrans - 1); |
801 | } | |
802 | } | |
803 | ||
9903cd1c CL |
804 | /** |
805 | * xprt_complete_rqst - called when reply processing is complete | |
1570c1e4 | 806 | * @task: RPC request that recently completed |
9903cd1c CL |
807 | * @copied: actual number of bytes received from the transport |
808 | * | |
1570c1e4 | 809 | * Caller holds transport lock. |
1da177e4 | 810 | */ |
1570c1e4 | 811 | void xprt_complete_rqst(struct rpc_task *task, int copied) |
1da177e4 | 812 | { |
1570c1e4 | 813 | struct rpc_rqst *req = task->tk_rqstp; |
fda13939 | 814 | struct rpc_xprt *xprt = req->rq_xprt; |
1da177e4 | 815 | |
1570c1e4 CL |
816 | dprintk("RPC: %5u xid %08x complete (%d bytes received)\n", |
817 | task->tk_pid, ntohl(req->rq_xid), copied); | |
3705ad64 | 818 | trace_xprt_complete_rqst(xprt, req->rq_xid, copied); |
1da177e4 | 819 | |
fda13939 | 820 | xprt->stat.recvs++; |
d60dbb20 | 821 | req->rq_rtt = ktime_sub(ktime_get(), req->rq_xtime); |
bbc72cea CL |
822 | if (xprt->ops->timer != NULL) |
823 | xprt_update_rtt(task); | |
ef759a2e | 824 | |
1da177e4 | 825 | list_del_init(&req->rq_list); |
1e799b67 | 826 | req->rq_private_buf.len = copied; |
dd2b63d0 RL |
827 | /* Ensure all writes are done before we update */ |
828 | /* req->rq_reply_bytes_recvd */ | |
43ac3f29 | 829 | smp_wmb(); |
dd2b63d0 | 830 | req->rq_reply_bytes_recvd = copied; |
fda13939 | 831 | rpc_wake_up_queued_task(&xprt->pending, task); |
1da177e4 | 832 | } |
12444809 | 833 | EXPORT_SYMBOL_GPL(xprt_complete_rqst); |
1da177e4 | 834 | |
46c0ee8b | 835 | static void xprt_timer(struct rpc_task *task) |
1da177e4 | 836 | { |
46c0ee8b | 837 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 LT |
838 | struct rpc_xprt *xprt = req->rq_xprt; |
839 | ||
5d00837b TM |
840 | if (task->tk_status != -ETIMEDOUT) |
841 | return; | |
46121cf7 | 842 | dprintk("RPC: %5u xprt_timer\n", task->tk_pid); |
1da177e4 | 843 | |
5d00837b | 844 | spin_lock_bh(&xprt->transport_lock); |
dd2b63d0 | 845 | if (!req->rq_reply_bytes_recvd) { |
46c0ee8b | 846 | if (xprt->ops->timer) |
6a24dfb6 | 847 | xprt->ops->timer(xprt, task); |
5d00837b TM |
848 | } else |
849 | task->tk_status = 0; | |
850 | spin_unlock_bh(&xprt->transport_lock); | |
1da177e4 LT |
851 | } |
852 | ||
4cfc7e60 RI |
853 | static inline int xprt_has_timer(struct rpc_xprt *xprt) |
854 | { | |
855 | return xprt->idle_timeout != 0; | |
856 | } | |
857 | ||
9903cd1c CL |
858 | /** |
859 | * xprt_prepare_transmit - reserve the transport before sending a request | |
860 | * @task: RPC task about to send a request | |
861 | * | |
1da177e4 | 862 | */ |
90051ea7 | 863 | bool xprt_prepare_transmit(struct rpc_task *task) |
1da177e4 LT |
864 | { |
865 | struct rpc_rqst *req = task->tk_rqstp; | |
866 | struct rpc_xprt *xprt = req->rq_xprt; | |
90051ea7 | 867 | bool ret = false; |
1da177e4 | 868 | |
46121cf7 | 869 | dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid); |
1da177e4 | 870 | |
4a0f8c04 | 871 | spin_lock_bh(&xprt->transport_lock); |
8a19a0b6 TM |
872 | if (!req->rq_bytes_sent) { |
873 | if (req->rq_reply_bytes_recvd) { | |
874 | task->tk_status = req->rq_reply_bytes_recvd; | |
875 | goto out_unlock; | |
876 | } | |
877 | if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT) | |
878 | && xprt_connected(xprt) | |
879 | && req->rq_connect_cookie == xprt->connect_cookie) { | |
880 | xprt->ops->set_retrans_timeout(task); | |
881 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
882 | goto out_unlock; | |
883 | } | |
1da177e4 | 884 | } |
90051ea7 TM |
885 | if (!xprt->ops->reserve_xprt(xprt, task)) { |
886 | task->tk_status = -EAGAIN; | |
887 | goto out_unlock; | |
888 | } | |
889 | ret = true; | |
1da177e4 | 890 | out_unlock: |
4a0f8c04 | 891 | spin_unlock_bh(&xprt->transport_lock); |
90051ea7 | 892 | return ret; |
1da177e4 LT |
893 | } |
894 | ||
e0ab53de | 895 | void xprt_end_transmit(struct rpc_task *task) |
5e5ce5be | 896 | { |
343952fa | 897 | xprt_release_write(task->tk_rqstp->rq_xprt, task); |
5e5ce5be TM |
898 | } |
899 | ||
9903cd1c CL |
900 | /** |
901 | * xprt_transmit - send an RPC request on a transport | |
902 | * @task: controlling RPC task | |
903 | * | |
904 | * We have to copy the iovec because sendmsg fiddles with its contents. | |
905 | */ | |
906 | void xprt_transmit(struct rpc_task *task) | |
1da177e4 | 907 | { |
1da177e4 LT |
908 | struct rpc_rqst *req = task->tk_rqstp; |
909 | struct rpc_xprt *xprt = req->rq_xprt; | |
15a45206 | 910 | int status, numreqs; |
1da177e4 | 911 | |
46121cf7 | 912 | dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); |
1da177e4 | 913 | |
dd2b63d0 | 914 | if (!req->rq_reply_bytes_recvd) { |
55ae1aab RL |
915 | if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { |
916 | /* | |
917 | * Add to the list only if we're expecting a reply | |
918 | */ | |
4a0f8c04 | 919 | spin_lock_bh(&xprt->transport_lock); |
1da177e4 LT |
920 | /* Update the softirq receive buffer */ |
921 | memcpy(&req->rq_private_buf, &req->rq_rcv_buf, | |
922 | sizeof(req->rq_private_buf)); | |
923 | /* Add request to the receive list */ | |
924 | list_add_tail(&req->rq_list, &xprt->recv); | |
4a0f8c04 | 925 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 | 926 | xprt_reset_majortimeo(req); |
0f9dc2b1 TM |
927 | /* Turn off autodisconnect */ |
928 | del_singleshot_timer_sync(&xprt->timer); | |
1da177e4 LT |
929 | } |
930 | } else if (!req->rq_bytes_sent) | |
931 | return; | |
932 | ||
ff839970 | 933 | req->rq_xtime = ktime_get(); |
a246b010 | 934 | status = xprt->ops->send_request(task); |
3705ad64 | 935 | trace_xprt_transmit(xprt, req->rq_xid, status); |
c8485e4d TM |
936 | if (status != 0) { |
937 | task->tk_status = status; | |
938 | return; | |
939 | } | |
262ca07d | 940 | |
c8485e4d | 941 | dprintk("RPC: %5u xmit complete\n", task->tk_pid); |
468f8613 | 942 | task->tk_flags |= RPC_TASK_SENT; |
c8485e4d | 943 | spin_lock_bh(&xprt->transport_lock); |
262ca07d | 944 | |
c8485e4d | 945 | xprt->ops->set_retrans_timeout(task); |
262ca07d | 946 | |
15a45206 AA |
947 | numreqs = atomic_read(&xprt->num_reqs); |
948 | if (numreqs > xprt->stat.max_slots) | |
949 | xprt->stat.max_slots = numreqs; | |
c8485e4d TM |
950 | xprt->stat.sends++; |
951 | xprt->stat.req_u += xprt->stat.sends - xprt->stat.recvs; | |
952 | xprt->stat.bklog_u += xprt->backlog.qlen; | |
15a45206 AA |
953 | xprt->stat.sending_u += xprt->sending.qlen; |
954 | xprt->stat.pending_u += xprt->pending.qlen; | |
1da177e4 | 955 | |
c8485e4d TM |
956 | /* Don't race with disconnect */ |
957 | if (!xprt_connected(xprt)) | |
958 | task->tk_status = -ENOTCONN; | |
0a660521 | 959 | else { |
55ae1aab RL |
960 | /* |
961 | * Sleep on the pending queue since | |
962 | * we're expecting a reply. | |
963 | */ | |
0a660521 TM |
964 | if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) |
965 | rpc_sleep_on(&xprt->pending, task, xprt_timer); | |
966 | req->rq_connect_cookie = xprt->connect_cookie; | |
55ae1aab | 967 | } |
c8485e4d | 968 | spin_unlock_bh(&xprt->transport_lock); |
1da177e4 LT |
969 | } |
970 | ||
ba60eb25 TM |
971 | static void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task) |
972 | { | |
973 | set_bit(XPRT_CONGESTED, &xprt->state); | |
974 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
975 | } | |
976 | ||
977 | static void xprt_wake_up_backlog(struct rpc_xprt *xprt) | |
978 | { | |
979 | if (rpc_wake_up_next(&xprt->backlog) == NULL) | |
980 | clear_bit(XPRT_CONGESTED, &xprt->state); | |
981 | } | |
982 | ||
983 | static bool xprt_throttle_congested(struct rpc_xprt *xprt, struct rpc_task *task) | |
984 | { | |
985 | bool ret = false; | |
986 | ||
987 | if (!test_bit(XPRT_CONGESTED, &xprt->state)) | |
988 | goto out; | |
989 | spin_lock(&xprt->reserve_lock); | |
990 | if (test_bit(XPRT_CONGESTED, &xprt->state)) { | |
991 | rpc_sleep_on(&xprt->backlog, task, NULL); | |
992 | ret = true; | |
993 | } | |
994 | spin_unlock(&xprt->reserve_lock); | |
995 | out: | |
996 | return ret; | |
997 | } | |
998 | ||
d9ba131d TM |
999 | static struct rpc_rqst *xprt_dynamic_alloc_slot(struct rpc_xprt *xprt, gfp_t gfp_flags) |
1000 | { | |
1001 | struct rpc_rqst *req = ERR_PTR(-EAGAIN); | |
1002 | ||
1003 | if (!atomic_add_unless(&xprt->num_reqs, 1, xprt->max_reqs)) | |
1004 | goto out; | |
1005 | req = kzalloc(sizeof(struct rpc_rqst), gfp_flags); | |
1006 | if (req != NULL) | |
1007 | goto out; | |
1008 | atomic_dec(&xprt->num_reqs); | |
1009 | req = ERR_PTR(-ENOMEM); | |
1010 | out: | |
1011 | return req; | |
1012 | } | |
1013 | ||
1014 | static bool xprt_dynamic_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) | |
1015 | { | |
1016 | if (atomic_add_unless(&xprt->num_reqs, -1, xprt->min_reqs)) { | |
1017 | kfree(req); | |
1018 | return true; | |
1019 | } | |
1020 | return false; | |
1021 | } | |
1022 | ||
f39c1bfb | 1023 | void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) |
1da177e4 | 1024 | { |
d9ba131d | 1025 | struct rpc_rqst *req; |
1da177e4 | 1026 | |
f39c1bfb | 1027 | spin_lock(&xprt->reserve_lock); |
1da177e4 | 1028 | if (!list_empty(&xprt->free)) { |
d9ba131d TM |
1029 | req = list_entry(xprt->free.next, struct rpc_rqst, rq_list); |
1030 | list_del(&req->rq_list); | |
1031 | goto out_init_req; | |
1032 | } | |
6b343099 | 1033 | req = xprt_dynamic_alloc_slot(xprt, GFP_NOWAIT|__GFP_NOWARN); |
d9ba131d TM |
1034 | if (!IS_ERR(req)) |
1035 | goto out_init_req; | |
1036 | switch (PTR_ERR(req)) { | |
1037 | case -ENOMEM: | |
d9ba131d TM |
1038 | dprintk("RPC: dynamic allocation of request slot " |
1039 | "failed! Retrying\n"); | |
1afeaf5c | 1040 | task->tk_status = -ENOMEM; |
d9ba131d TM |
1041 | break; |
1042 | case -EAGAIN: | |
ba60eb25 | 1043 | xprt_add_backlog(xprt, task); |
d9ba131d | 1044 | dprintk("RPC: waiting for request slot\n"); |
1afeaf5c TM |
1045 | default: |
1046 | task->tk_status = -EAGAIN; | |
1da177e4 | 1047 | } |
f39c1bfb | 1048 | spin_unlock(&xprt->reserve_lock); |
d9ba131d TM |
1049 | return; |
1050 | out_init_req: | |
1051 | task->tk_status = 0; | |
1052 | task->tk_rqstp = req; | |
1053 | xprt_request_init(task, xprt); | |
f39c1bfb TM |
1054 | spin_unlock(&xprt->reserve_lock); |
1055 | } | |
1056 | EXPORT_SYMBOL_GPL(xprt_alloc_slot); | |
1057 | ||
1058 | void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task) | |
1059 | { | |
1060 | /* Note: grabbing the xprt_lock_write() ensures that we throttle | |
1061 | * new slot allocation if the transport is congested (i.e. when | |
1062 | * reconnecting a stream transport or when out of socket write | |
1063 | * buffer space). | |
1064 | */ | |
1065 | if (xprt_lock_write(xprt, task)) { | |
1066 | xprt_alloc_slot(xprt, task); | |
1067 | xprt_release_write(xprt, task); | |
1068 | } | |
1da177e4 | 1069 | } |
f39c1bfb | 1070 | EXPORT_SYMBOL_GPL(xprt_lock_and_alloc_slot); |
1da177e4 | 1071 | |
ee5ebe85 TM |
1072 | static void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req) |
1073 | { | |
ee5ebe85 | 1074 | spin_lock(&xprt->reserve_lock); |
c25573b5 TM |
1075 | if (!xprt_dynamic_free_slot(xprt, req)) { |
1076 | memset(req, 0, sizeof(*req)); /* mark unused */ | |
1077 | list_add(&req->rq_list, &xprt->free); | |
1078 | } | |
ba60eb25 | 1079 | xprt_wake_up_backlog(xprt); |
ee5ebe85 TM |
1080 | spin_unlock(&xprt->reserve_lock); |
1081 | } | |
1082 | ||
21de0a95 TM |
1083 | static void xprt_free_all_slots(struct rpc_xprt *xprt) |
1084 | { | |
1085 | struct rpc_rqst *req; | |
1086 | while (!list_empty(&xprt->free)) { | |
1087 | req = list_first_entry(&xprt->free, struct rpc_rqst, rq_list); | |
1088 | list_del(&req->rq_list); | |
1089 | kfree(req); | |
1090 | } | |
1091 | } | |
1092 | ||
d9ba131d TM |
1093 | struct rpc_xprt *xprt_alloc(struct net *net, size_t size, |
1094 | unsigned int num_prealloc, | |
1095 | unsigned int max_alloc) | |
bd1722d4 PE |
1096 | { |
1097 | struct rpc_xprt *xprt; | |
21de0a95 TM |
1098 | struct rpc_rqst *req; |
1099 | int i; | |
bd1722d4 PE |
1100 | |
1101 | xprt = kzalloc(size, GFP_KERNEL); | |
1102 | if (xprt == NULL) | |
1103 | goto out; | |
1104 | ||
21de0a95 TM |
1105 | xprt_init(xprt, net); |
1106 | ||
1107 | for (i = 0; i < num_prealloc; i++) { | |
1108 | req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL); | |
1109 | if (!req) | |
8313164c | 1110 | goto out_free; |
21de0a95 TM |
1111 | list_add(&req->rq_list, &xprt->free); |
1112 | } | |
d9ba131d TM |
1113 | if (max_alloc > num_prealloc) |
1114 | xprt->max_reqs = max_alloc; | |
1115 | else | |
1116 | xprt->max_reqs = num_prealloc; | |
1117 | xprt->min_reqs = num_prealloc; | |
1118 | atomic_set(&xprt->num_reqs, num_prealloc); | |
bd1722d4 PE |
1119 | |
1120 | return xprt; | |
1121 | ||
1122 | out_free: | |
21de0a95 | 1123 | xprt_free(xprt); |
bd1722d4 PE |
1124 | out: |
1125 | return NULL; | |
1126 | } | |
1127 | EXPORT_SYMBOL_GPL(xprt_alloc); | |
1128 | ||
e204e621 PE |
1129 | void xprt_free(struct rpc_xprt *xprt) |
1130 | { | |
37aa2133 | 1131 | put_net(xprt->xprt_net); |
21de0a95 | 1132 | xprt_free_all_slots(xprt); |
e204e621 PE |
1133 | kfree(xprt); |
1134 | } | |
1135 | EXPORT_SYMBOL_GPL(xprt_free); | |
1136 | ||
9903cd1c CL |
1137 | /** |
1138 | * xprt_reserve - allocate an RPC request slot | |
1139 | * @task: RPC task requesting a slot allocation | |
1140 | * | |
ba60eb25 TM |
1141 | * If the transport is marked as being congested, or if no more |
1142 | * slots are available, place the task on the transport's | |
9903cd1c CL |
1143 | * backlog queue. |
1144 | */ | |
1145 | void xprt_reserve(struct rpc_task *task) | |
1da177e4 | 1146 | { |
45bc0dce | 1147 | struct rpc_xprt *xprt; |
1da177e4 | 1148 | |
43cedbf0 TM |
1149 | task->tk_status = 0; |
1150 | if (task->tk_rqstp != NULL) | |
1151 | return; | |
1152 | ||
43cedbf0 TM |
1153 | task->tk_timeout = 0; |
1154 | task->tk_status = -EAGAIN; | |
45bc0dce TM |
1155 | rcu_read_lock(); |
1156 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
ba60eb25 TM |
1157 | if (!xprt_throttle_congested(xprt, task)) |
1158 | xprt->ops->alloc_slot(xprt, task); | |
1159 | rcu_read_unlock(); | |
1160 | } | |
1161 | ||
1162 | /** | |
1163 | * xprt_retry_reserve - allocate an RPC request slot | |
1164 | * @task: RPC task requesting a slot allocation | |
1165 | * | |
1166 | * If no more slots are available, place the task on the transport's | |
1167 | * backlog queue. | |
1168 | * Note that the only difference with xprt_reserve is that we now | |
1169 | * ignore the value of the XPRT_CONGESTED flag. | |
1170 | */ | |
1171 | void xprt_retry_reserve(struct rpc_task *task) | |
1172 | { | |
1173 | struct rpc_xprt *xprt; | |
1174 | ||
1175 | task->tk_status = 0; | |
1176 | if (task->tk_rqstp != NULL) | |
1177 | return; | |
1178 | ||
1179 | task->tk_timeout = 0; | |
1180 | task->tk_status = -EAGAIN; | |
1181 | rcu_read_lock(); | |
1182 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
f39c1bfb | 1183 | xprt->ops->alloc_slot(xprt, task); |
45bc0dce | 1184 | rcu_read_unlock(); |
1da177e4 LT |
1185 | } |
1186 | ||
d8ed029d | 1187 | static inline __be32 xprt_alloc_xid(struct rpc_xprt *xprt) |
1da177e4 | 1188 | { |
0eae88f3 | 1189 | return (__force __be32)xprt->xid++; |
1da177e4 LT |
1190 | } |
1191 | ||
1192 | static inline void xprt_init_xid(struct rpc_xprt *xprt) | |
1193 | { | |
63862b5b | 1194 | xprt->xid = prandom_u32(); |
1da177e4 LT |
1195 | } |
1196 | ||
9903cd1c | 1197 | static void xprt_request_init(struct rpc_task *task, struct rpc_xprt *xprt) |
1da177e4 LT |
1198 | { |
1199 | struct rpc_rqst *req = task->tk_rqstp; | |
1200 | ||
d9ba131d | 1201 | INIT_LIST_HEAD(&req->rq_list); |
ba7392bb | 1202 | req->rq_timeout = task->tk_client->cl_timeout->to_initval; |
1da177e4 LT |
1203 | req->rq_task = task; |
1204 | req->rq_xprt = xprt; | |
02107148 | 1205 | req->rq_buffer = NULL; |
1da177e4 | 1206 | req->rq_xid = xprt_alloc_xid(xprt); |
0a660521 | 1207 | req->rq_connect_cookie = xprt->connect_cookie - 1; |
92551948 TM |
1208 | req->rq_bytes_sent = 0; |
1209 | req->rq_snd_buf.len = 0; | |
1210 | req->rq_snd_buf.buflen = 0; | |
1211 | req->rq_rcv_buf.len = 0; | |
1212 | req->rq_rcv_buf.buflen = 0; | |
ead5e1c2 | 1213 | req->rq_release_snd_buf = NULL; |
da45828e | 1214 | xprt_reset_majortimeo(req); |
46121cf7 | 1215 | dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid, |
1da177e4 LT |
1216 | req, ntohl(req->rq_xid)); |
1217 | } | |
1218 | ||
9903cd1c CL |
1219 | /** |
1220 | * xprt_release - release an RPC request slot | |
1221 | * @task: task which is finished with the slot | |
1222 | * | |
1da177e4 | 1223 | */ |
9903cd1c | 1224 | void xprt_release(struct rpc_task *task) |
1da177e4 | 1225 | { |
55ae1aab | 1226 | struct rpc_xprt *xprt; |
87ed5003 | 1227 | struct rpc_rqst *req = task->tk_rqstp; |
1da177e4 | 1228 | |
87ed5003 TM |
1229 | if (req == NULL) { |
1230 | if (task->tk_client) { | |
1231 | rcu_read_lock(); | |
1232 | xprt = rcu_dereference(task->tk_client->cl_xprt); | |
1233 | if (xprt->snd_task == task) | |
1234 | xprt_release_write(xprt, task); | |
1235 | rcu_read_unlock(); | |
1236 | } | |
1da177e4 | 1237 | return; |
87ed5003 | 1238 | } |
55ae1aab | 1239 | |
55ae1aab | 1240 | xprt = req->rq_xprt; |
0a702195 WAA |
1241 | if (task->tk_ops->rpc_count_stats != NULL) |
1242 | task->tk_ops->rpc_count_stats(task, task->tk_calldata); | |
1243 | else if (task->tk_client) | |
1244 | rpc_count_iostats(task, task->tk_client->cl_metrics); | |
4a0f8c04 | 1245 | spin_lock_bh(&xprt->transport_lock); |
49e9a890 | 1246 | xprt->ops->release_xprt(xprt, task); |
a58dd398 CL |
1247 | if (xprt->ops->release_request) |
1248 | xprt->ops->release_request(task); | |
1da177e4 LT |
1249 | if (!list_empty(&req->rq_list)) |
1250 | list_del(&req->rq_list); | |
1251 | xprt->last_used = jiffies; | |
4cfc7e60 | 1252 | if (list_empty(&xprt->recv) && xprt_has_timer(xprt)) |
a246b010 | 1253 | mod_timer(&xprt->timer, |
03bf4b70 | 1254 | xprt->last_used + xprt->idle_timeout); |
4a0f8c04 | 1255 | spin_unlock_bh(&xprt->transport_lock); |
ee5ebe85 | 1256 | if (req->rq_buffer) |
55ae1aab | 1257 | xprt->ops->buf_free(req->rq_buffer); |
a17c2153 TM |
1258 | if (req->rq_cred != NULL) |
1259 | put_rpccred(req->rq_cred); | |
1da177e4 | 1260 | task->tk_rqstp = NULL; |
ead5e1c2 BF |
1261 | if (req->rq_release_snd_buf) |
1262 | req->rq_release_snd_buf(req); | |
55ae1aab | 1263 | |
46121cf7 | 1264 | dprintk("RPC: %5u release request %p\n", task->tk_pid, req); |
ee5ebe85 TM |
1265 | if (likely(!bc_prealloc(req))) |
1266 | xprt_free_slot(xprt, req); | |
1267 | else | |
c9acb42e | 1268 | xprt_free_bc_request(req); |
1da177e4 LT |
1269 | } |
1270 | ||
21de0a95 | 1271 | static void xprt_init(struct rpc_xprt *xprt, struct net *net) |
c2866763 | 1272 | { |
21de0a95 | 1273 | atomic_set(&xprt->count, 1); |
c2866763 CL |
1274 | |
1275 | spin_lock_init(&xprt->transport_lock); | |
1276 | spin_lock_init(&xprt->reserve_lock); | |
1277 | ||
1278 | INIT_LIST_HEAD(&xprt->free); | |
1279 | INIT_LIST_HEAD(&xprt->recv); | |
9e00abc3 | 1280 | #if defined(CONFIG_SUNRPC_BACKCHANNEL) |
f9acac1a RL |
1281 | spin_lock_init(&xprt->bc_pa_lock); |
1282 | INIT_LIST_HEAD(&xprt->bc_pa_list); | |
9e00abc3 | 1283 | #endif /* CONFIG_SUNRPC_BACKCHANNEL */ |
f9acac1a | 1284 | |
c2866763 CL |
1285 | xprt->last_used = jiffies; |
1286 | xprt->cwnd = RPC_INITCWND; | |
a509050b | 1287 | xprt->bind_index = 0; |
c2866763 CL |
1288 | |
1289 | rpc_init_wait_queue(&xprt->binding, "xprt_binding"); | |
1290 | rpc_init_wait_queue(&xprt->pending, "xprt_pending"); | |
34006cee | 1291 | rpc_init_priority_wait_queue(&xprt->sending, "xprt_sending"); |
c2866763 CL |
1292 | rpc_init_priority_wait_queue(&xprt->backlog, "xprt_backlog"); |
1293 | ||
c2866763 CL |
1294 | xprt_init_xid(xprt); |
1295 | ||
21de0a95 | 1296 | xprt->xprt_net = get_net(net); |
8d9266ff TM |
1297 | } |
1298 | ||
1299 | /** | |
1300 | * xprt_create_transport - create an RPC transport | |
1301 | * @args: rpc transport creation arguments | |
1302 | * | |
1303 | */ | |
1304 | struct rpc_xprt *xprt_create_transport(struct xprt_create *args) | |
1305 | { | |
388f0c77 | 1306 | int err; |
8d9266ff TM |
1307 | struct rpc_xprt *xprt; |
1308 | struct xprt_class *t; | |
1309 | ||
1310 | spin_lock(&xprt_list_lock); | |
1311 | list_for_each_entry(t, &xprt_list, list) { | |
1312 | if (t->ident == args->ident) { | |
1313 | spin_unlock(&xprt_list_lock); | |
1314 | goto found; | |
1315 | } | |
1316 | } | |
1317 | spin_unlock(&xprt_list_lock); | |
3c45ddf8 | 1318 | dprintk("RPC: transport (%d) not supported\n", args->ident); |
8d9266ff TM |
1319 | return ERR_PTR(-EIO); |
1320 | ||
1321 | found: | |
1322 | xprt = t->setup(args); | |
1323 | if (IS_ERR(xprt)) { | |
1324 | dprintk("RPC: xprt_create_transport: failed, %ld\n", | |
1325 | -PTR_ERR(xprt)); | |
21de0a95 | 1326 | goto out; |
8d9266ff | 1327 | } |
33d90ac0 BF |
1328 | if (args->flags & XPRT_CREATE_NO_IDLE_TIMEOUT) |
1329 | xprt->idle_timeout = 0; | |
21de0a95 TM |
1330 | INIT_WORK(&xprt->task_cleanup, xprt_autoclose); |
1331 | if (xprt_has_timer(xprt)) | |
1332 | setup_timer(&xprt->timer, xprt_init_autodisconnect, | |
1333 | (unsigned long)xprt); | |
1334 | else | |
1335 | init_timer(&xprt->timer); | |
4e0038b6 TM |
1336 | |
1337 | if (strlen(args->servername) > RPC_MAXNETNAMELEN) { | |
1338 | xprt_destroy(xprt); | |
1339 | return ERR_PTR(-EINVAL); | |
1340 | } | |
1341 | xprt->servername = kstrdup(args->servername, GFP_KERNEL); | |
1342 | if (xprt->servername == NULL) { | |
1343 | xprt_destroy(xprt); | |
1344 | return ERR_PTR(-ENOMEM); | |
1345 | } | |
1346 | ||
388f0c77 JL |
1347 | err = rpc_xprt_debugfs_register(xprt); |
1348 | if (err) { | |
1349 | xprt_destroy(xprt); | |
1350 | return ERR_PTR(err); | |
1351 | } | |
1352 | ||
46121cf7 | 1353 | dprintk("RPC: created transport %p with %u slots\n", xprt, |
c2866763 | 1354 | xprt->max_reqs); |
21de0a95 | 1355 | out: |
c2866763 CL |
1356 | return xprt; |
1357 | } | |
1358 | ||
9903cd1c CL |
1359 | /** |
1360 | * xprt_destroy - destroy an RPC transport, killing off all requests. | |
a8de240a | 1361 | * @xprt: transport to destroy |
9903cd1c | 1362 | * |
1da177e4 | 1363 | */ |
a8de240a | 1364 | static void xprt_destroy(struct rpc_xprt *xprt) |
1da177e4 | 1365 | { |
46121cf7 | 1366 | dprintk("RPC: destroying transport %p\n", xprt); |
0065db32 | 1367 | del_timer_sync(&xprt->timer); |
c8541ecd | 1368 | |
388f0c77 | 1369 | rpc_xprt_debugfs_unregister(xprt); |
f6a1cc89 TM |
1370 | rpc_destroy_wait_queue(&xprt->binding); |
1371 | rpc_destroy_wait_queue(&xprt->pending); | |
1372 | rpc_destroy_wait_queue(&xprt->sending); | |
f6a1cc89 | 1373 | rpc_destroy_wait_queue(&xprt->backlog); |
c3ae62ae | 1374 | cancel_work_sync(&xprt->task_cleanup); |
4e0038b6 | 1375 | kfree(xprt->servername); |
c8541ecd CL |
1376 | /* |
1377 | * Tear down transport state and free the rpc_xprt | |
1378 | */ | |
a246b010 | 1379 | xprt->ops->destroy(xprt); |
6b6ca86b | 1380 | } |
1da177e4 | 1381 | |
6b6ca86b TM |
1382 | /** |
1383 | * xprt_put - release a reference to an RPC transport. | |
1384 | * @xprt: pointer to the transport | |
1385 | * | |
1386 | */ | |
1387 | void xprt_put(struct rpc_xprt *xprt) | |
1388 | { | |
a8de240a TM |
1389 | if (atomic_dec_and_test(&xprt->count)) |
1390 | xprt_destroy(xprt); | |
6b6ca86b | 1391 | } |