1 /*-
2  * Copyright (c) 2017 Mellanox Technologies, Ltd.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef _LINUXKPI_LINUX_MM_TYPES_H_
30 #define	_LINUXKPI_LINUX_MM_TYPES_H_
31 
32 #include <linux/types.h>
33 #include <linux/page.h>
34 #include <linux/rwsem.h>
35 
36 #include <asm/atomic.h>
37 
38 typedef int vm_fault_t;
39 
40 struct vm_area_struct;
41 struct task_struct;
42 
43 struct mm_struct {
44 	struct vm_area_struct *mmap;
45 	atomic_t mm_count;
46 	atomic_t mm_users;
47 	size_t pinned_vm;
48 	/* Renamed to mmap_lock in v5.8 */
49 	struct rw_semaphore mmap_sem;
50 };
51 
52 extern void linux_mm_dtor(struct mm_struct *mm);
53 
54 static inline void
55 mmdrop(struct mm_struct *mm)
56 {
57 	if (__predict_false(atomic_dec_and_test(&mm->mm_count)))
58 		linux_mm_dtor(mm);
59 }
60 
61 static inline bool
62 mmget_not_zero(struct mm_struct *mm)
63 {
64 	return (atomic_inc_not_zero(&mm->mm_users));
65 }
66 
67 static inline void
68 mmput(struct mm_struct *mm)
69 {
70 	if (__predict_false(atomic_dec_and_test(&mm->mm_users)))
71 		mmdrop(mm);
72 }
73 
74 static inline void
75 mmgrab(struct mm_struct *mm)
76 {
77 	atomic_inc(&mm->mm_count);
78 }
79 
80 extern struct mm_struct *linux_get_task_mm(struct task_struct *);
81 #define	get_task_mm(task) linux_get_task_mm(task)
82 
83 #endif					/* _LINUXKPI_LINUX_MM_TYPES_H_ */
84