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 */
24struct rpc_procinfo;
25struct 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
32struct rpc_call_ops;
33struct rpc_wait_queue;
34struct 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 describes a timeout strategy
42 */
43struct rpc_timeout {
44 unsigned long to_initval, /* initial timeout */
45 to_maxval, /* max timeout */
46 to_increment; /* if !exponential */
47 unsigned int to_retries; /* max # of retries */
48 unsigned char to_exponential;
49};
50
51/*
52 * This is the RPC task struct
53 */
54struct rpc_task {
55 atomic_t tk_count; /* Reference count */
56 int tk_status; /* result of last operation */
57 struct list_head tk_task; /* global list of tasks */
58
59 /*
60 * callback to be executed after waking up
61 * action next procedure for async tasks
62 */
63 void (*tk_callback)(struct rpc_task *);
64 void (*tk_action)(struct rpc_task *);
65
66 unsigned long tk_timeout; /* timeout for rpc_sleep() */
67 unsigned long tk_runstate; /* Task run status */
68
69 struct rpc_wait_queue *tk_waitqueue; /* RPC wait queue we're on */
70 union {
71 struct work_struct tk_work; /* Async task work queue */
72 struct rpc_wait tk_wait; /* RPC wait */
73 } u;
74
75 /*
76 * RPC call state
77 */
78 struct rpc_message tk_msg; /* RPC call info */
79 void * tk_calldata; /* Caller private data */
80 const struct rpc_call_ops *tk_ops; /* Caller callbacks */
81
82 struct rpc_clnt * tk_client; /* RPC client */
83 struct rpc_xprt * tk_xprt; /* Transport */
84 struct rpc_cred * tk_op_cred; /* cred being operated on */
85
86 struct rpc_rqst * tk_rqstp; /* RPC request */
87
88 struct workqueue_struct *tk_workqueue; /* Normally rpciod, but could
89 * be any workqueue
90 */
91 ktime_t tk_start; /* RPC task init timestamp */
92
93 pid_t tk_owner; /* Process id for batching tasks */
94
95 int tk_rpc_status; /* Result of last RPC operation */
96 unsigned short tk_flags; /* misc flags */
97 unsigned short tk_timeouts; /* maj timeouts */
98
99#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
100 unsigned short tk_pid; /* debugging aid */
101#endif
102 unsigned char tk_priority : 2,/* Task priority */
103 tk_garb_retry : 2,
104 tk_cred_retry : 2;
105};
106
107typedef void (*rpc_action)(struct rpc_task *);
108
109struct rpc_call_ops {
110 void (*rpc_call_prepare)(struct rpc_task *, void *);
111 void (*rpc_call_done)(struct rpc_task *, void *);
112 void (*rpc_count_stats)(struct rpc_task *, void *);
113 void (*rpc_release)(void *);
114};
115
116struct rpc_task_setup {
117 struct rpc_task *task;
118 struct rpc_clnt *rpc_client;
119 struct rpc_xprt *rpc_xprt;
120 struct rpc_cred *rpc_op_cred; /* credential being operated on */
121 const struct rpc_message *rpc_message;
122 const struct rpc_call_ops *callback_ops;
123 void *callback_data;
124 struct workqueue_struct *workqueue;
125 unsigned short flags;
126 signed char priority;
127};
128
129/*
130 * RPC task flags
131 */
132#define RPC_TASK_ASYNC 0x0001 /* is an async task */
133#define RPC_TASK_SWAPPER 0x0002 /* is swapping in/out */
134#define RPC_TASK_MOVEABLE 0x0004 /* nfs4.1+ rpc tasks */
135#define RPC_TASK_NULLCREDS 0x0010 /* Use AUTH_NULL credential */
136#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
137#define RPC_TASK_NETUNREACH_FATAL 0x0040 /* ENETUNREACH is fatal */
138#define RPC_TASK_DYNAMIC 0x0080 /* task was kmalloc'ed */
139#define RPC_TASK_NO_ROUND_ROBIN 0x0100 /* send requests on "main" xprt */
140#define RPC_TASK_SOFT 0x0200 /* Use soft timeouts */
141#define RPC_TASK_SOFTCONN 0x0400 /* Fail if can't connect */
142#define RPC_TASK_SENT 0x0800 /* message was sent */
143#define RPC_TASK_TIMEOUT 0x1000 /* fail with ETIMEDOUT on timeout */
144#define RPC_TASK_NOCONNECT 0x2000 /* return ENOTCONN if not connected */
145#define RPC_TASK_NO_RETRANS_TIMEOUT 0x4000 /* wait forever for a reply */
146#define RPC_TASK_CRED_NOREF 0x8000 /* No refcount on the credential */
147
148#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
149#define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
150#define RPC_IS_SOFT(t) ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
151#define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN)
152#define RPC_WAS_SENT(t) ((t)->tk_flags & RPC_TASK_SENT)
153#define RPC_IS_MOVEABLE(t) ((t)->tk_flags & RPC_TASK_MOVEABLE)
154
155enum {
156 RPC_TASK_RUNNING,
157 RPC_TASK_QUEUED,
158 RPC_TASK_ACTIVE,
159 RPC_TASK_NEED_XMIT,
160 RPC_TASK_NEED_RECV,
161 RPC_TASK_MSG_PIN_WAIT,
162};
163
164#define rpc_test_and_set_running(t) \
165 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
166#define rpc_clear_running(t) clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
167
168#define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
169#define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
170#define rpc_clear_queued(t) clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
171
172#define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
173
174#define RPC_SIGNALLED(t) (READ_ONCE(task->tk_rpc_status) == -ERESTARTSYS)
175
176/*
177 * Task priorities.
178 * Note: if you change these, you must also change
179 * the task initialization definitions below.
180 */
181#define RPC_PRIORITY_LOW (-1)
182#define RPC_PRIORITY_NORMAL (0)
183#define RPC_PRIORITY_HIGH (1)
184#define RPC_PRIORITY_PRIVILEGED (2)
185#define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
186
187struct rpc_timer {
188 struct list_head list;
189 unsigned long expires;
190 struct delayed_work dwork;
191};
192
193/*
194 * RPC synchronization objects
195 */
196struct rpc_wait_queue {
197 spinlock_t lock;
198 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
199 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
200 unsigned char priority; /* current priority */
201 unsigned char nr; /* # tasks remaining for cookie */
202 unsigned int qlen; /* total # tasks waiting in queue */
203 struct rpc_timer timer_list;
204#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
205 const char * name;
206#endif
207};
208
209/*
210 * This is the # requests to send consecutively
211 * from a single cookie. The aim is to improve
212 * performance of NFS operations such as read/write.
213 */
214#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
215
216/*
217 * Function prototypes
218 */
219struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
220struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
221struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req,
222 struct rpc_timeout *timeout);
223void rpc_put_task(struct rpc_task *);
224void rpc_put_task_async(struct rpc_task *);
225bool rpc_task_set_rpc_status(struct rpc_task *task, int rpc_status);
226void rpc_task_try_cancel(struct rpc_task *task, int error);
227void rpc_signal_task(struct rpc_task *);
228void rpc_exit_task(struct rpc_task *);
229void rpc_exit(struct rpc_task *, int);
230void rpc_release_calldata(const struct rpc_call_ops *, void *);
231void rpc_killall_tasks(struct rpc_clnt *);
232unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
233 bool (*fnmatch)(const struct rpc_task *,
234 const void *),
235 const void *data);
236void rpc_execute(struct rpc_task *);
237void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
238void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
239void rpc_destroy_wait_queue(struct rpc_wait_queue *);
240unsigned long rpc_task_timeout(const struct rpc_task *task);
241void rpc_sleep_on_timeout(struct rpc_wait_queue *queue,
242 struct rpc_task *task,
243 rpc_action action,
244 unsigned long timeout);
245void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
246 rpc_action action);
247void rpc_sleep_on_priority_timeout(struct rpc_wait_queue *queue,
248 struct rpc_task *task,
249 unsigned long timeout,
250 int priority);
251void rpc_sleep_on_priority(struct rpc_wait_queue *,
252 struct rpc_task *,
253 int priority);
254void rpc_wake_up_queued_task(struct rpc_wait_queue *,
255 struct rpc_task *);
256void rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
257 struct rpc_task *,
258 int);
259void rpc_wake_up(struct rpc_wait_queue *);
260struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
261struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
262 struct rpc_wait_queue *,
263 bool (*)(struct rpc_task *, void *),
264 void *);
265struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
266 bool (*)(struct rpc_task *, void *),
267 void *);
268void rpc_wake_up_status(struct rpc_wait_queue *, int);
269void rpc_delay(struct rpc_task *, unsigned long);
270int rpc_malloc(struct rpc_task *);
271void rpc_free(struct rpc_task *);
272int rpciod_up(void);
273void rpciod_down(void);
274int rpc_wait_for_completion_task(struct rpc_task *task);
275#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
276struct net;
277void rpc_show_tasks(struct net *);
278#endif
279int rpc_init_mempool(void);
280void rpc_destroy_mempool(void);
281extern struct workqueue_struct *rpciod_workqueue;
282extern struct workqueue_struct *xprtiod_workqueue;
283void rpc_prepare_task(struct rpc_task *task);
284gfp_t rpc_task_gfp_mask(void);
285
286#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
287static inline const char * rpc_qname(const struct rpc_wait_queue *q)
288{
289 return ((q && q->name) ? q->name : "unknown");
290}
291
292static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
293 const char *name)
294{
295 q->name = name;
296}
297#else
298static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
299 const char *name)
300{
301}
302#endif
303
304#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
305int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
306void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
307#else
308static inline int
309rpc_clnt_swap_activate(struct rpc_clnt *clnt)
310{
311 return -EINVAL;
312}
313
314static inline void
315rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
316{
317}
318#endif /* CONFIG_SUNRPC_SWAP */
319
320#endif /* _LINUX_SUNRPC_SCHED_H_ */
321

source code of linux/include/linux/sunrpc/sched.h