1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * linux/include/linux/sunrpc/sched.h
4 *
5 * Scheduling primitives for kernel Sun RPC.
6 *
7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
8 */
9
10 #ifndef _LINUX_SUNRPC_SCHED_H_
11 #define _LINUX_SUNRPC_SCHED_H_
12
13 #include <linux/timer.h>
14 #include <linux/ktime.h>
15 #include <linux/sunrpc/types.h>
16 #include <linux/spinlock.h>
17 #include <linux/wait_bit.h>
18 #include <linux/workqueue.h>
19 #include <linux/sunrpc/xdr.h>
20
21 /*
22 * This is the actual RPC procedure call info.
23 */
24 struct rpc_procinfo;
25 struct rpc_message {
26 const struct rpc_procinfo *rpc_proc; /* Procedure information */
27 void * rpc_argp; /* Arguments */
28 void * rpc_resp; /* Result */
29 const struct cred * rpc_cred; /* Credentials */
30 };
31
32 struct rpc_call_ops;
33 struct rpc_wait_queue;
34 struct rpc_wait {
35 struct list_head list; /* wait queue links */
36 struct list_head links; /* Links to related tasks */
37 struct list_head timer_list; /* Timer list */
38 };
39
40 /*
41 * This is the RPC task struct
42 */
43 struct rpc_task {
44 atomic_t tk_count; /* Reference count */
45 int tk_status; /* result of last operation */
46 struct list_head tk_task; /* global list of tasks */
47
48 /*
49 * callback to be executed after waking up
50 * action next procedure for async tasks
51 */
52 void (*tk_callback)(struct rpc_task *);
53 void (*tk_action)(struct rpc_task *);
54
55 unsigned long tk_timeout; /* timeout for rpc_sleep() */
56 unsigned long tk_runstate; /* Task run status */
57
58 struct rpc_wait_queue *tk_waitqueue; /* RPC wait queue we're on */
59 union {
60 struct work_struct tk_work; /* Async task work queue */
61 struct rpc_wait tk_wait; /* RPC wait */
62 } u;
63
64 int tk_rpc_status; /* Result of last RPC operation */
65
66 /*
67 * RPC call state
68 */
69 struct rpc_message tk_msg; /* RPC call info */
70 void * tk_calldata; /* Caller private data */
71 const struct rpc_call_ops *tk_ops; /* Caller callbacks */
72
73 struct rpc_clnt * tk_client; /* RPC client */
74 struct rpc_xprt * tk_xprt; /* Transport */
75 struct rpc_cred * tk_op_cred; /* cred being operated on */
76
77 struct rpc_rqst * tk_rqstp; /* RPC request */
78
79 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
80 * be any workqueue
81 */
82 ktime_t tk_start; /* RPC task init timestamp */
83
84 pid_t tk_owner; /* Process id for batching tasks */
85 unsigned short tk_flags; /* misc flags */
86 unsigned short tk_timeouts; /* maj timeouts */
87
88 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
89 unsigned short tk_pid; /* debugging aid */
90 #endif
91 unsigned char tk_priority : 2,/* Task priority */
92 tk_garb_retry : 2,
93 tk_cred_retry : 2;
94 };
95
96 typedef void (*rpc_action)(struct rpc_task *);
97
98 struct rpc_call_ops {
99 void (*rpc_call_prepare)(struct rpc_task *, void *);
100 void (*rpc_call_done)(struct rpc_task *, void *);
101 void (*rpc_count_stats)(struct rpc_task *, void *);
102 void (*rpc_release)(void *);
103 };
104
105 struct rpc_task_setup {
106 struct rpc_task *task;
107 struct rpc_clnt *rpc_client;
108 struct rpc_xprt *rpc_xprt;
109 struct rpc_cred *rpc_op_cred; /* credential being operated on */
110 const struct rpc_message *rpc_message;
111 const struct rpc_call_ops *callback_ops;
112 void *callback_data;
113 struct workqueue_struct *workqueue;
114 unsigned short flags;
115 signed char priority;
116 };
117
118 /*
119 * RPC task flags
120 */
121 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
122 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
123 #define RPC_TASK_NULLCREDS 0x0010 /* Use AUTH_NULL credential */
124 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
125 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
126 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
127 #define RPC_TASK_NO_ROUND_ROBIN 0x0100 /* send requests on "main" xprt */
128 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
129 #define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */
130 #define RPC_TASK_SENT 0x0800 /* message was sent */
131 #define RPC_TASK_TIMEOUT 0x1000 /* fail with ETIMEDOUT on timeout */
132 #define RPC_TASK_NOCONNECT 0x2000 /* return ENOTCONN if not connected */
133 #define RPC_TASK_NO_RETRANS_TIMEOUT 0x4000 /* wait forever for a reply */
134
135 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
136 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
137 #define RPC_IS_SOFT(t) ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
138 #define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN)
139 #define RPC_WAS_SENT(t) ((t)->tk_flags & RPC_TASK_SENT)
140
141 #define RPC_TASK_RUNNING 0
142 #define RPC_TASK_QUEUED 1
143 #define RPC_TASK_ACTIVE 2
144 #define RPC_TASK_NEED_XMIT 3
145 #define RPC_TASK_NEED_RECV 4
146 #define RPC_TASK_MSG_PIN_WAIT 5
147 #define RPC_TASK_SIGNALLED 6
148
149 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
150 #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
151 #define rpc_test_and_set_running(t) \
152 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
153 #define rpc_clear_running(t) \
154 do { \
155 smp_mb__before_atomic(); \
156 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
157 smp_mb__after_atomic(); \
158 } while (0)
159
160 #define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
161 #define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
162 #define rpc_clear_queued(t) \
163 do { \
164 smp_mb__before_atomic(); \
165 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
166 smp_mb__after_atomic(); \
167 } while (0)
168
169 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
170
171 #define RPC_SIGNALLED(t) test_bit(RPC_TASK_SIGNALLED, &(t)->tk_runstate)
172
173 /*
174 * Task priorities.
175 * Note: if you change these, you must also change
176 * the task initialization definitions below.
177 */
178 #define RPC_PRIORITY_LOW (-1)
179 #define RPC_PRIORITY_NORMAL (0)
180 #define RPC_PRIORITY_HIGH (1)
181 #define RPC_PRIORITY_PRIVILEGED (2)
182 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
183
184 struct rpc_timer {
185 struct list_head list;
186 unsigned long expires;
187 struct delayed_work dwork;
188 };
189
190 /*
191 * RPC synchronization objects
192 */
193 struct rpc_wait_queue {
194 spinlock_t lock;
195 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
196 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
197 unsigned char priority; /* current priority */
198 unsigned char nr; /* # tasks remaining for cookie */
199 unsigned int qlen; /* total # tasks waiting in queue */
200 struct rpc_timer timer_list;
201 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
202 const char * name;
203 #endif
204 };
205
206 /*
207 * This is the # requests to send consecutively
208 * from a single cookie. The aim is to improve
209 * performance of NFS operations such as read/write.
210 */
211 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
212
213 /*
214 * Function prototypes
215 */
216 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
217 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
218 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
219 void rpc_put_task(struct rpc_task *);
220 void rpc_put_task_async(struct rpc_task *);
221 void rpc_signal_task(struct rpc_task *);
222 void rpc_exit_task(struct rpc_task *);
223 void rpc_exit(struct rpc_task *, int);
224 void rpc_release_calldata(const struct rpc_call_ops *, void *);
225 void rpc_killall_tasks(struct rpc_clnt *);
226 void rpc_execute(struct rpc_task *);
227 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
228 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
229 void rpc_destroy_wait_queue(struct rpc_wait_queue *);
230 unsigned long rpc_task_timeout(const struct rpc_task *task);
231 void rpc_sleep_on_timeout(struct rpc_wait_queue *queue,
232 struct rpc_task *task,
233 rpc_action action,
234 unsigned long timeout);
235 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
236 rpc_action action);
237 void rpc_sleep_on_priority_timeout(struct rpc_wait_queue *queue,
238 struct rpc_task *task,
239 unsigned long timeout,
240 int priority);
241 void rpc_sleep_on_priority(struct rpc_wait_queue *,
242 struct rpc_task *,
243 int priority);
244 void rpc_wake_up_queued_task(struct rpc_wait_queue *,
245 struct rpc_task *);
246 void rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
247 struct rpc_task *,
248 int);
249 void rpc_wake_up(struct rpc_wait_queue *);
250 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
251 struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
252 struct rpc_wait_queue *,
253 bool (*)(struct rpc_task *, void *),
254 void *);
255 struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
256 bool (*)(struct rpc_task *, void *),
257 void *);
258 void rpc_wake_up_status(struct rpc_wait_queue *, int);
259 void rpc_delay(struct rpc_task *, unsigned long);
260 int rpc_malloc(struct rpc_task *);
261 void rpc_free(struct rpc_task *);
262 int rpciod_up(void);
263 void rpciod_down(void);
264 int __rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *);
265 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
266 struct net;
267 void rpc_show_tasks(struct net *);
268 #endif
269 int rpc_init_mempool(void);
270 void rpc_destroy_mempool(void);
271 extern struct workqueue_struct *rpciod_workqueue;
272 extern struct workqueue_struct *xprtiod_workqueue;
273 void rpc_prepare_task(struct rpc_task *task);
274
rpc_wait_for_completion_task(struct rpc_task * task)275 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
276 {
277 return __rpc_wait_for_completion_task(task, NULL);
278 }
279
280 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
rpc_qname(const struct rpc_wait_queue * q)281 static inline const char * rpc_qname(const struct rpc_wait_queue *q)
282 {
283 return ((q && q->name) ? q->name : "unknown");
284 }
285
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)286 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
287 const char *name)
288 {
289 q->name = name;
290 }
291 #else
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)292 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
293 const char *name)
294 {
295 }
296 #endif
297
298 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
299 int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
300 void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
301 #else
302 static inline int
rpc_clnt_swap_activate(struct rpc_clnt * clnt)303 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
304 {
305 return -EINVAL;
306 }
307
308 static inline void
rpc_clnt_swap_deactivate(struct rpc_clnt * clnt)309 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
310 {
311 }
312 #endif /* CONFIG_SUNRPC_SWAP */
313
314 #endif /* _LINUX_SUNRPC_SCHED_H_ */
315