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