1/*
2 * linux/include/linux/sunrpc/sched.h
3 *
4 * Scheduling primitives for kernel Sun RPC.
5 *
6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
7 */
8
9#ifndef _LINUX_SUNRPC_SCHED_H_
10#define _LINUX_SUNRPC_SCHED_H_
11
12#include <linux/timer.h>
13#include <linux/tqueue.h>
14#include <linux/sunrpc/types.h>
15#include <linux/wait.h>
16
17/*
18 * Define this if you want to test the fast scheduler for async calls.
19 * This is still experimental and may not work.
20 */
21#undef  CONFIG_RPC_FASTSCHED
22
23/*
24 * This is the actual RPC procedure call info.
25 */
26struct rpc_message {
27	__u32			rpc_proc;	/* Procedure number */
28	void *			rpc_argp;	/* Arguments */
29	void *			rpc_resp;	/* Result */
30	struct rpc_cred *	rpc_cred;	/* Credentials */
31};
32
33/*
34 * This is the RPC task struct
35 */
36struct rpc_task {
37	struct list_head	tk_list;	/* wait queue links */
38#ifdef RPC_DEBUG
39	unsigned long		tk_magic;	/* 0xf00baa */
40#endif
41	struct list_head	tk_task;	/* global list of tasks */
42	struct rpc_clnt *	tk_client;	/* RPC client */
43	struct rpc_rqst *	tk_rqstp;	/* RPC request */
44	int			tk_status;	/* result of last operation */
45	struct rpc_wait_queue *	tk_rpcwait;	/* RPC wait queue we're on */
46
47	/*
48	 * RPC call state
49	 */
50	struct rpc_message	tk_msg;		/* RPC call info */
51	__u32 *			tk_buffer;	/* XDR buffer */
52	__u8			tk_garb_retry,
53				tk_cred_retry,
54				tk_suid_retry;
55
56	/*
57	 * timeout_fn   to be executed by timer bottom half
58	 * callback	to be executed after waking up
59	 * action	next procedure for async tasks
60	 * exit		exit async task and report to caller
61	 */
62	void			(*tk_timeout_fn)(struct rpc_task *);
63	void			(*tk_callback)(struct rpc_task *);
64	void			(*tk_action)(struct rpc_task *);
65	void			(*tk_exit)(struct rpc_task *);
66	void			(*tk_release)(struct rpc_task *);
67	void *			tk_calldata;
68
69	/*
70	 * tk_timer is used for async processing by the RPC scheduling
71	 * primitives. You should not access this directly unless
72	 * you have a pathological interest in kernel oopses.
73	 */
74	struct timer_list	tk_timer;	/* kernel timer */
75	wait_queue_head_t	tk_wait;	/* sync: sleep on this q */
76	unsigned long		tk_timeout;	/* timeout for rpc_sleep() */
77	unsigned short		tk_flags;	/* misc flags */
78	unsigned char		tk_active   : 1;/* Task has been activated */
79	unsigned long		tk_runstate;	/* Task run status */
80#ifdef RPC_DEBUG
81	unsigned short		tk_pid;		/* debugging aid */
82#endif
83};
84#define tk_auth			tk_client->cl_auth
85#define tk_xprt			tk_client->cl_xprt
86
87/* support walking a list of tasks on a wait queue */
88#define	task_for_each(task, pos, head) \
89	list_for_each(pos, head) \
90		if ((task=list_entry(pos, struct rpc_task, tk_list)),1)
91
92#define	task_for_first(task, head) \
93	if (!list_empty(head) &&  \
94	    ((task=list_entry((head)->next, struct rpc_task, tk_list)),1))
95
96/* .. and walking list of all tasks */
97#define	alltask_for_each(task, pos, head) \
98	list_for_each(pos, head) \
99		if ((task=list_entry(pos, struct rpc_task, tk_task)),1)
100
101typedef void			(*rpc_action)(struct rpc_task *);
102
103/*
104 * RPC task flags
105 */
106#define RPC_TASK_ASYNC		0x0001		/* is an async task */
107#define RPC_TASK_SWAPPER	0x0002		/* is swapping in/out */
108#define RPC_TASK_SETUID		0x0004		/* is setuid process */
109#define RPC_TASK_CHILD		0x0008		/* is child of other task */
110#define RPC_CALL_REALUID	0x0010		/* try using real uid */
111#define RPC_CALL_MAJORSEEN	0x0020		/* major timeout seen */
112#define RPC_TASK_ROOTCREDS	0x0040		/* force root creds */
113#define RPC_TASK_DYNAMIC	0x0080		/* task was kmalloc'ed */
114#define RPC_TASK_KILLED		0x0100		/* task was killed */
115
116#define RPC_IS_ASYNC(t)		((t)->tk_flags & RPC_TASK_ASYNC)
117#define RPC_IS_SETUID(t)	((t)->tk_flags & RPC_TASK_SETUID)
118#define RPC_IS_CHILD(t)		((t)->tk_flags & RPC_TASK_CHILD)
119#define RPC_IS_SWAPPER(t)	((t)->tk_flags & RPC_TASK_SWAPPER)
120#define RPC_DO_ROOTOVERRIDE(t)	((t)->tk_flags & RPC_TASK_ROOTCREDS)
121#define RPC_ASSASSINATED(t)	((t)->tk_flags & RPC_TASK_KILLED)
122#define RPC_IS_ACTIVATED(t)	((t)->tk_active)
123#define RPC_DO_CALLBACK(t)	((t)->tk_callback != NULL)
124
125#define RPC_TASK_SLEEPING	0
126#define RPC_TASK_RUNNING	1
127#define RPC_IS_SLEEPING(t)	(test_bit(RPC_TASK_SLEEPING, &(t)->tk_runstate))
128#define RPC_IS_RUNNING(t)	(test_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
129
130#define rpc_set_running(t)	(set_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
131#define rpc_clear_running(t)	(clear_bit(RPC_TASK_RUNNING, &(t)->tk_runstate))
132
133#define rpc_set_sleeping(t)	(set_bit(RPC_TASK_SLEEPING, &(t)->tk_runstate))
134
135#define rpc_clear_sleeping(t) \
136	do { \
137		smp_mb__before_clear_bit(); \
138		clear_bit(RPC_TASK_SLEEPING, &(t)->tk_runstate); \
139		smp_mb__after_clear_bit(); \
140	} while(0)
141
142/*
143 * RPC synchronization objects
144 */
145struct rpc_wait_queue {
146	struct list_head	tasks;
147#ifdef RPC_DEBUG
148	char *			name;
149#endif
150};
151
152#ifndef RPC_DEBUG
153# define RPC_WAITQ_INIT(var,qname) ((struct rpc_wait_queue) {LIST_HEAD_INIT(var)})
154# define RPC_WAITQ(var,qname)      struct rpc_wait_queue var = RPC_WAITQ_INIT(var.tasks,qname)
155# define INIT_RPC_WAITQ(ptr,qname) do { \
156	INIT_LIST_HEAD(&(ptr)->tasks); \
157	} while(0)
158#else
159# define RPC_WAITQ_INIT(var,qname) ((struct rpc_wait_queue) {LIST_HEAD_INIT(var.tasks), qname})
160# define RPC_WAITQ(var,qname)      struct rpc_wait_queue var = RPC_WAITQ_INIT(var,qname)
161# define INIT_RPC_WAITQ(ptr,qname) do { \
162	INIT_LIST_HEAD(&(ptr)->tasks); (ptr)->name = qname; \
163	} while(0)
164#endif
165
166/*
167 * Function prototypes
168 */
169struct rpc_task *rpc_new_task(struct rpc_clnt *, rpc_action, int flags);
170struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent);
171void		rpc_init_task(struct rpc_task *, struct rpc_clnt *,
172					rpc_action exitfunc, int flags);
173void		rpc_release_task(struct rpc_task *);
174void		rpc_killall_tasks(struct rpc_clnt *);
175int		rpc_execute(struct rpc_task *);
176void		rpc_run_child(struct rpc_task *parent, struct rpc_task *child,
177					rpc_action action);
178int		rpc_add_wait_queue(struct rpc_wait_queue *, struct rpc_task *);
179void		rpc_remove_wait_queue(struct rpc_task *);
180void		rpc_sleep_on(struct rpc_wait_queue *, struct rpc_task *,
181					rpc_action action, rpc_action timer);
182void		rpc_add_timer(struct rpc_task *, rpc_action);
183void		rpc_wake_up_task(struct rpc_task *);
184void		rpc_wake_up(struct rpc_wait_queue *);
185struct rpc_task *rpc_wake_up_next(struct rpc_wait_queue *);
186void		rpc_wake_up_status(struct rpc_wait_queue *, int);
187void		rpc_delay(struct rpc_task *, unsigned long);
188void *		rpc_allocate(unsigned int flags, unsigned int);
189void		rpc_free(void *);
190int		rpciod_up(void);
191void		rpciod_down(void);
192void		rpciod_wake_up(void);
193#ifdef RPC_DEBUG
194void		rpc_show_tasks(void);
195#endif
196
197static __inline__ void *
198rpc_malloc(struct rpc_task *task, unsigned int size)
199{
200	return rpc_allocate(task->tk_flags, size);
201}
202
203static __inline__ void
204rpc_exit(struct rpc_task *task, int status)
205{
206	task->tk_status = status;
207	task->tk_action = NULL;
208}
209
210#ifdef RPC_DEBUG
211static __inline__ char *
212rpc_qname(struct rpc_wait_queue *q)
213{
214	return q->name? q->name : "unknown";
215}
216#endif
217
218#endif /* _LINUX_SUNRPC_SCHED_H_ */
219