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 is the RPC task struct
42 */
43struct 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 /*
65 * RPC call state
66 */
67 struct rpc_message tk_msg; /* RPC call info */
68 void * tk_calldata; /* Caller private data */
69 const struct rpc_call_ops *tk_ops; /* Caller callbacks */
70
71 struct rpc_clnt * tk_client; /* RPC client */
72 struct rpc_xprt * tk_xprt; /* Transport */
73 struct rpc_cred * tk_op_cred; /* cred being operated on */
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
84 int tk_rpc_status; /* Result of last RPC operation */
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
96typedef void (*rpc_action)(struct rpc_task *);
97
98struct 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
105struct 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_MOVEABLE 0x0004 /* nfs4.1+ rpc tasks */
124#define RPC_TASK_NULLCREDS 0x0010 /* Use AUTH_NULL credential */
125#define RPC_CALL_MAJORSEEN 0x0020 /* major timeout seen */
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#define RPC_TASK_CRED_NOREF 0x8000 /* No refcount on the credential */
135
136#define RPC_IS_ASYNC(t) ((t)->tk_flags & RPC_TASK_ASYNC)
137#define RPC_IS_SWAPPER(t) ((t)->tk_flags & RPC_TASK_SWAPPER)
138#define RPC_IS_SOFT(t) ((t)->tk_flags & (RPC_TASK_SOFT|RPC_TASK_TIMEOUT))
139#define RPC_IS_SOFTCONN(t) ((t)->tk_flags & RPC_TASK_SOFTCONN)
140#define RPC_WAS_SENT(t) ((t)->tk_flags & RPC_TASK_SENT)
141#define RPC_IS_MOVEABLE(t) ((t)->tk_flags & RPC_TASK_MOVEABLE)
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_test_and_set_running(t) \
152 test_and_set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
153#define rpc_clear_running(t) clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate)
154
155#define RPC_IS_QUEUED(t) test_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
156#define rpc_set_queued(t) set_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
157#define rpc_clear_queued(t) clear_bit(RPC_TASK_QUEUED, &(t)->tk_runstate)
158
159#define RPC_IS_ACTIVATED(t) test_bit(RPC_TASK_ACTIVE, &(t)->tk_runstate)
160
161#define RPC_SIGNALLED(t) test_bit(RPC_TASK_SIGNALLED, &(t)->tk_runstate)
162
163/*
164 * Task priorities.
165 * Note: if you change these, you must also change
166 * the task initialization definitions below.
167 */
168#define RPC_PRIORITY_LOW (-1)
169#define RPC_PRIORITY_NORMAL (0)
170#define RPC_PRIORITY_HIGH (1)
171#define RPC_PRIORITY_PRIVILEGED (2)
172#define RPC_NR_PRIORITY (1 + RPC_PRIORITY_PRIVILEGED - RPC_PRIORITY_LOW)
173
174struct rpc_timer {
175 struct list_head list;
176 unsigned long expires;
177 struct delayed_work dwork;
178};
179
180/*
181 * RPC synchronization objects
182 */
183struct rpc_wait_queue {
184 spinlock_t lock;
185 struct list_head tasks[RPC_NR_PRIORITY]; /* task queue for each priority level */
186 unsigned char maxpriority; /* maximum priority (0 if queue is not a priority queue) */
187 unsigned char priority; /* current priority */
188 unsigned char nr; /* # tasks remaining for cookie */
189 unsigned short qlen; /* total # tasks waiting in queue */
190 struct rpc_timer timer_list;
191#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
192 const char * name;
193#endif
194};
195
196/*
197 * This is the # requests to send consecutively
198 * from a single cookie. The aim is to improve
199 * performance of NFS operations such as read/write.
200 */
201#define RPC_IS_PRIORITY(q) ((q)->maxpriority > 0)
202
203/*
204 * Function prototypes
205 */
206struct rpc_task *rpc_new_task(const struct rpc_task_setup *);
207struct rpc_task *rpc_run_task(const struct rpc_task_setup *);
208struct rpc_task *rpc_run_bc_task(struct rpc_rqst *req);
209void rpc_put_task(struct rpc_task *);
210void rpc_put_task_async(struct rpc_task *);
211bool rpc_task_set_rpc_status(struct rpc_task *task, int rpc_status);
212void rpc_task_try_cancel(struct rpc_task *task, int error);
213void rpc_signal_task(struct rpc_task *);
214void rpc_exit_task(struct rpc_task *);
215void rpc_exit(struct rpc_task *, int);
216void rpc_release_calldata(const struct rpc_call_ops *, void *);
217void rpc_killall_tasks(struct rpc_clnt *);
218unsigned long rpc_cancel_tasks(struct rpc_clnt *clnt, int error,
219 bool (*fnmatch)(const struct rpc_task *,
220 const void *),
221 const void *data);
222void rpc_execute(struct rpc_task *);
223void rpc_init_priority_wait_queue(struct rpc_wait_queue *, const char *);
224void rpc_init_wait_queue(struct rpc_wait_queue *, const char *);
225void rpc_destroy_wait_queue(struct rpc_wait_queue *);
226unsigned long rpc_task_timeout(const struct rpc_task *task);
227void rpc_sleep_on_timeout(struct rpc_wait_queue *queue,
228 struct rpc_task *task,
229 rpc_action action,
230 unsigned long timeout);
231void rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
232 rpc_action action);
233void rpc_sleep_on_priority_timeout(struct rpc_wait_queue *queue,
234 struct rpc_task *task,
235 unsigned long timeout,
236 int priority);
237void rpc_sleep_on_priority(struct rpc_wait_queue *,
238 struct rpc_task *,
239 int priority);
240void rpc_wake_up_queued_task(struct rpc_wait_queue *,
241 struct rpc_task *);
242void rpc_wake_up_queued_task_set_status(struct rpc_wait_queue *,
243 struct rpc_task *,
244 int);
245void rpc_wake_up(struct rpc_wait_queue *);
246struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
247struct rpc_task *rpc_wake_up_first_on_wq(struct workqueue_struct *wq,
248 struct rpc_wait_queue *,
249 bool (*)(struct rpc_task *, void *),
250 void *);
251struct rpc_task *rpc_wake_up_first(struct rpc_wait_queue *,
252 bool (*)(struct rpc_task *, void *),
253 void *);
254void rpc_wake_up_status(struct rpc_wait_queue *, int);
255void rpc_delay(struct rpc_task *, unsigned long);
256int rpc_malloc(struct rpc_task *);
257void rpc_free(struct rpc_task *);
258int rpciod_up(void);
259void rpciod_down(void);
260int rpc_wait_for_completion_task(struct rpc_task *task);
261#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
262struct net;
263void rpc_show_tasks(struct net *);
264#endif
265int rpc_init_mempool(void);
266void rpc_destroy_mempool(void);
267extern struct workqueue_struct *rpciod_workqueue;
268extern struct workqueue_struct *xprtiod_workqueue;
269void rpc_prepare_task(struct rpc_task *task);
270gfp_t rpc_task_gfp_mask(void);
271
272#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) || IS_ENABLED(CONFIG_TRACEPOINTS)
273static inline const char * rpc_qname(const struct rpc_wait_queue *q)
274{
275 return ((q && q->name) ? q->name : "unknown");
276}
277
278static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
279 const char *name)
280{
281 q->name = name;
282}
283#else
284static inline void rpc_assign_waitqueue_name(struct rpc_wait_queue *q,
285 const char *name)
286{
287}
288#endif
289
290#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
291int rpc_clnt_swap_activate(struct rpc_clnt *clnt);
292void rpc_clnt_swap_deactivate(struct rpc_clnt *clnt);
293#else
294static inline int
295rpc_clnt_swap_activate(struct rpc_clnt *clnt)
296{
297 return -EINVAL;
298}
299
300static inline void
301rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
302{
303}
304#endif /* CONFIG_SUNRPC_SWAP */
305
306#endif /* _LINUX_SUNRPC_SCHED_H_ */
307

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