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 tk_rebind_retry : 2;
95 };
96
97 typedef void (*rpc_action)(struct rpc_task *);
98
99 struct rpc_call_ops {
100 void (*rpc_call_prepare)(struct rpc_task *, void *);
101 void (*rpc_call_done)(struct rpc_task *, void *);
102 void (*rpc_count_stats)(struct rpc_task *, void *);
103 void (*rpc_release)(void *);
104 };
105
106 struct rpc_task_setup {
107 struct rpc_task *task;
108 struct rpc_clnt *rpc_client;
109 struct rpc_xprt *rpc_xprt;
110 struct rpc_cred *rpc_op_cred; /* credential being operated on */
111 const struct rpc_message *rpc_message;
112 const struct rpc_call_ops *callback_ops;
113 void *callback_data;
114 struct workqueue_struct *workqueue;
115 unsigned short flags;
116 signed char priority;
117 };
118
119 /*
120 * RPC task flags
121 */
122 #define RPC_TASK_ASYNC 0x0001 /* is an async task */
123 #define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
124 #define RPC_TASK_NULLCREDS 0x0010 /* Use AUTH_NULL credential */
125 #define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
126 #define RPC_TASK_ROOTCREDS 0x0040 /* force root creds */
127 #define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
128 #define RPC_TASK_NO_ROUND_ROBIN 0x0100 /* send requests on "main" xprt */
129 #define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
130 #define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */
131 #define RPC_TASK_SENT 0x0800 /* message was sent */
132 #define RPC_TASK_TIMEOUT 0x1000 /* fail with ETIMEDOUT on timeout */
133 #define RPC_TASK_NOCONNECT 0x2000 /* return ENOTCONN if not connected */
134 #define RPC_TASK_NO_RETRANS_TIMEOUT 0x4000 /* wait forever for a reply */
135 #define RPC_TASK_CRED_NOREF 0x8000 /* No refcount on the credential */
136
137 #define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
138 #define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
139 #define RPC_IS_SOFT(t) ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
140 #define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN)
141 #define RPC_WAS_SENT(t) ((t)->tk_flags & RPC_TASK_SENT)
142
143 #define RPC_TASK_RUNNING 0
144 #define RPC_TASK_QUEUED 1
145 #define RPC_TASK_ACTIVE 2
146 #define RPC_TASK_NEED_XMIT 3
147 #define RPC_TASK_NEED_RECV 4
148 #define RPC_TASK_MSG_PIN_WAIT 5
149 #define RPC_TASK_SIGNALLED 6
150
151 #define RPC_IS_RUNNING(t) test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
152 #define rpc_set_running(t) set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
153 #define rpc_test_and_set_running(t) \
154 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
155 #define rpc_clear_running(t) \
156 do { \
157 smp_mb__before_atomic(); \
158 clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate); \
159 smp_mb__after_atomic(); \
160 } while (0)
161
162 #define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
163 #define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
164 #define rpc_clear_queued(t) \
165 do { \
166 smp_mb__before_atomic(); \
167 clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate); \
168 smp_mb__after_atomic(); \
169 } while (0)
170
171 #define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
172
173 #define RPC_SIGNALLED(t) test_bit(RPC_TASK_SIGNALLED, &(t)->tk_runstate)
174
175 /*
176 * Task priorities.
177 * Note: if you change these, you must also change
178 * the task initialization definitions below.
179 */
180 #define RPC_PRIORITY_LOW (-1)
181 #define RPC_PRIORITY_NORMAL (0)
182 #define RPC_PRIORITY_HIGH (1)
183 #define RPC_PRIORITY_PRIVILEGED (2)
184 #define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
185
186 struct rpc_timer {
187 struct list_head list;
188 unsigned long expires;
189 struct delayed_work dwork;
190 };
191
192 /*
193 * RPC synchronization objects
194 */
195 struct rpc_wait_queue {
196 spinlock_t lock;
197 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
198 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
199 unsigned char priority; /* current priority */
200 unsigned char nr; /* # tasks remaining for cookie */
201 unsigned short qlen; /* total # tasks waiting in queue */
202 struct rpc_timer timer_list;
203 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
204 const char * name;
205 #endif
206 };
207
208 /*
209 * This is the # requests to send consecutively
210 * from a single cookie. The aim is to improve
211 * performance of NFS operations such as read/write.
212 */
213 #define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
214
215 /*
216 * Function prototypes
217 */
218 struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
219 struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
220 struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
221 void rpc_put_task(struct rpc_task *);
222 void rpc_put_task_async(struct rpc_task *);
223 void rpc_signal_task(struct rpc_task *);
224 void rpc_exit_task(struct rpc_task *);
225 void rpc_exit(struct rpc_task *, int);
226 void rpc_release_calldata(const struct rpc_call_ops *, void *);
227 void rpc_killall_tasks(struct rpc_clnt *);
228 void rpc_execute(struct rpc_task *);
229 void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
230 void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
231 void rpc_destroy_wait_queue(struct rpc_wait_queue *);
232 unsigned long rpc_task_timeout(const struct rpc_task *task);
233 void rpc_sleep_on_timeout(struct rpc_wait_queue *queue,
234 struct rpc_task *task,
235 rpc_action action,
236 unsigned long timeout);
237 void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
238 rpc_action action);
239 void rpc_sleep_on_priority_timeout(struct rpc_wait_queue *queue,
240 struct rpc_task *task,
241 unsigned long timeout,
242 int priority);
243 void rpc_sleep_on_priority(struct rpc_wait_queue *,
244 struct rpc_task *,
245 int priority);
246 void rpc_wake_up_queued_task(struct rpc_wait_queue *,
247 struct rpc_task *);
248 void rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
249 struct rpc_task *,
250 int);
251 void rpc_wake_up(struct rpc_wait_queue *);
252 struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
253 struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
254 struct rpc_wait_queue *,
255 bool (*)(struct rpc_task *, void *),
256 void *);
257 struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
258 bool (*)(struct rpc_task *, void *),
259 void *);
260 void rpc_wake_up_status(struct rpc_wait_queue *, int);
261 void rpc_delay(struct rpc_task *, unsigned long);
262 int rpc_malloc(struct rpc_task *);
263 void rpc_free(struct rpc_task *);
264 int rpciod_up(void);
265 void rpciod_down(void);
266 int __rpc_wait_for_completion_task(struct rpc_task *task, wait_bit_action_f *);
267 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
268 struct net;
269 void rpc_show_tasks(struct net *);
270 #endif
271 int rpc_init_mempool(void);
272 void rpc_destroy_mempool(void);
273 extern struct workqueue_struct *rpciod_workqueue;
274 extern struct workqueue_struct *xprtiod_workqueue;
275 void rpc_prepare_task(struct rpc_task *task);
276
rpc_wait_for_completion_task(struct rpc_task * task)277 static inline int rpc_wait_for_completion_task(struct rpc_task *task)
278 {
279 return __rpc_wait_for_completion_task(task, NULL);
280 }
281
282 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
rpc_qname(const struct rpc_wait_queue * q)283 static inline const char * rpc_qname(const struct rpc_wait_queue *q)
284 {
285 return ((q && q->name) ? q->name : "unknown");
286 }
287
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)288 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
289 const char *name)
290 {
291 q->name = name;
292 }
293 #else
rpc_assign_waitqueue_name(struct rpc_wait_queue * q,const char * name)294 static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
295 const char *name)
296 {
297 }
298 #endif
299
300 #if IS_ENABLED(CONFIG_SUNRPC_SWAP)
301 int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
302 void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
303 #else
304 static inline int
rpc_clnt_swap_activate(struct rpc_clnt * clnt)305 rpc_clnt_swap_activate(struct rpc_clnt *clnt)
306 {
307 return -EINVAL;
308 }
309
310 static inline void
rpc_clnt_swap_deactivate(struct rpc_clnt * clnt)311 rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
312 {
313 }
314 #endif /* CONFIG_SUNRPC_SWAP */
315
316 #endif /* _LINUX_SUNRPC_SCHED_H_ */
317
