1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2018 Mellanox Technologies, Ltd.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice unmodified, this list of conditions, and the following
13  *    disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 #ifndef	_LINUX_SCHED_H_
32 #define	_LINUX_SCHED_H_
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/proc.h>
37 #include <sys/sched.h>
38 #include <sys/sleepqueue.h>
39 #include <sys/time.h>
40 
41 #include <linux/bitmap.h>
42 #include <linux/compat.h>
43 #include <linux/completion.h>
44 #include <linux/mm_types.h>
45 #include <linux/pid.h>
46 #include <linux/slab.h>
47 #include <linux/string.h>
48 #include <linux/time.h>
49 
50 #include <asm/atomic.h>
51 
52 #define	MAX_SCHEDULE_TIMEOUT	INT_MAX
53 
54 #define	TASK_RUNNING		0x0000
55 #define	TASK_INTERRUPTIBLE	0x0001
56 #define	TASK_UNINTERRUPTIBLE	0x0002
57 #define	TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
58 #define	TASK_WAKING		0x0100
59 #define	TASK_PARKED		0x0200
60 
61 #define	TASK_COMM_LEN		(MAXCOMLEN + 1)
62 
63 struct work_struct;
64 struct task_struct {
65 	struct thread *task_thread;
66 	struct mm_struct *mm;
67 	linux_task_fn_t *task_fn;
68 	void   *task_data;
69 	int	task_ret;
70 	atomic_t usage;
71 	atomic_t state;
72 	atomic_t kthread_flags;
73 	pid_t	pid;	/* BSD thread ID */
74 	const char    *comm;
75 	void   *bsd_ioctl_data;
76 	unsigned bsd_ioctl_len;
77 	struct completion parked;
78 	struct completion exited;
79 	TAILQ_ENTRY(task_struct) rcu_entry;
80 	int rcu_recurse;
81 	int bsd_interrupt_value;
82 	struct work_struct *work;	/* current work struct, if set */
83 	struct task_struct *group_leader;
84 };
85 
86 #define	current	({ \
87 	struct thread *__td = curthread; \
88 	linux_set_current(__td); \
89 	((struct task_struct *)__td->td_lkpi_task); \
90 })
91 
92 #define	task_pid_group_leader(task) (task)->task_thread->td_proc->p_pid
93 #define	task_pid(task)		((task)->pid)
94 #define	task_pid_nr(task)	((task)->pid)
95 #define	task_pid_vnr(task)	((task)->pid)
96 #define	get_pid(x)		(x)
97 #define	put_pid(x)		do { } while (0)
98 #define	current_euid()	(curthread->td_ucred->cr_uid)
99 #define	task_euid(task)	((task)->task_thread->td_ucred->cr_uid)
100 
101 #define	get_task_state(task)		atomic_read(&(task)->state)
102 #define	set_task_state(task, x)		atomic_set(&(task)->state, (x))
103 #define	__set_task_state(task, x)	((task)->state.counter = (x))
104 #define	set_current_state(x)		set_task_state(current, x)
105 #define	__set_current_state(x)		__set_task_state(current, x)
106 
107 static inline void
108 get_task_struct(struct task_struct *task)
109 {
110 	atomic_inc(&task->usage);
111 }
112 
113 static inline void
114 put_task_struct(struct task_struct *task)
115 {
116 	if (atomic_dec_and_test(&task->usage))
117 		linux_free_current(task);
118 }
119 
120 #define	cond_resched()	do { if (!cold) sched_relinquish(curthread); } while (0)
121 
122 #define	yield()		kern_yield(PRI_UNCHANGED)
123 #define	sched_yield()	sched_relinquish(curthread)
124 
125 #define	need_resched() (curthread->td_flags & TDF_NEEDRESCHED)
126 
127 bool linux_signal_pending(struct task_struct *task);
128 bool linux_fatal_signal_pending(struct task_struct *task);
129 bool linux_signal_pending_state(long state, struct task_struct *task);
130 void linux_send_sig(int signo, struct task_struct *task);
131 
132 #define	signal_pending(task)		linux_signal_pending(task)
133 #define	fatal_signal_pending(task)	linux_fatal_signal_pending(task)
134 #define	signal_pending_state(state, task)		\
135 	linux_signal_pending_state(state, task)
136 #define	send_sig(signo, task, priv) do {		\
137 	CTASSERT((priv) == 0);				\
138 	linux_send_sig(signo, task);			\
139 } while (0)
140 
141 int linux_schedule_timeout(int timeout);
142 
143 static inline void
144 linux_schedule_save_interrupt_value(struct task_struct *task, int value)
145 {
146 	task->bsd_interrupt_value = value;
147 }
148 
149 bool linux_task_exiting(struct task_struct *task);
150 
151 #define	current_exiting() \
152 	linux_task_exiting(current)
153 
154 static inline int
155 linux_schedule_get_interrupt_value(struct task_struct *task)
156 {
157 	int value = task->bsd_interrupt_value;
158 	task->bsd_interrupt_value = 0;
159 	return (value);
160 }
161 
162 #define	schedule()					\
163 	(void)linux_schedule_timeout(MAX_SCHEDULE_TIMEOUT)
164 #define	schedule_timeout(timeout)			\
165 	linux_schedule_timeout(timeout)
166 #define	schedule_timeout_killable(timeout)		\
167 	schedule_timeout_interruptible(timeout)
168 #define	schedule_timeout_interruptible(timeout) ({	\
169 	set_current_state(TASK_INTERRUPTIBLE);		\
170 	schedule_timeout(timeout);			\
171 })
172 #define	schedule_timeout_uninterruptible(timeout) ({	\
173 	set_current_state(TASK_UNINTERRUPTIBLE);	\
174 	schedule_timeout(timeout);			\
175 })
176 
177 #define	io_schedule()			schedule()
178 #define	io_schedule_timeout(timeout)	schedule_timeout(timeout)
179 
180 static inline uint64_t
181 local_clock(void)
182 {
183 	struct timespec ts;
184 
185 	nanotime(&ts);
186 	return ((uint64_t)ts.tv_sec * NSEC_PER_SEC + ts.tv_nsec);
187 }
188 
189 static inline const char *
190 get_task_comm(char *buf, struct task_struct *task)
191 {
192 
193 	buf[0] = 0; /* buffer is too small */
194 	return (task->comm);
195 }
196 
197 #endif	/* _LINUX_SCHED_H_ */
198