xref: /illumos-gate/usr/src/uts/common/sys/kmem.h (revision ed093b41)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright (c) 2012 by Delphix. All rights reserved.
25  * Copyright 2013 Nexenta Systems, Inc.  All rights reserved.
26  * Copyright 2022 Joyent, Inc.
27  */
28 
29 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
30 /*	  All Rights Reserved	*/
31 
32 #ifndef _SYS_KMEM_H
33 #define	_SYS_KMEM_H
34 
35 #include <sys/types.h>
36 #include <sys/vmem.h>
37 
38 #ifdef	__cplusplus
39 extern "C" {
40 #endif
41 
42 /*
43  * Kernel memory allocator: DDI interfaces.
44  * See kmem_alloc(9F) for details.
45  */
46 
47 #define	KM_SLEEP	0x0000	/* can block for memory; success guaranteed */
48 #define	KM_NOSLEEP	0x0001	/* cannot block for memory; may fail */
49 #define	KM_PANIC	0x0002	/* if memory cannot be allocated, panic */
50 #define	KM_PUSHPAGE	0x0004	/* can block for memory; may use reserve */
51 #define	KM_NORMALPRI	0x0008  /* with KM_NOSLEEP, lower priority allocation */
52 #define	KM_NOSLEEP_LAZY	(KM_NOSLEEP | KM_NORMALPRI)  /* Syntactic sugar. */
53 #define	KM_VMFLAGS	0x00ff	/* flags that must match VM_* flags */
54 
55 #define	KM_FLAGS	0xffff	/* all settable kmem flags */
56 
57 #if defined(_KERNEL) || defined(_FAKE_KERNEL)
58 
59 extern void *kmem_alloc(size_t size, int kmflags);
60 extern void *kmem_zalloc(size_t size, int kmflags);
61 extern void kmem_free(void *buf, size_t size);
62 extern void *kmem_alloc_tryhard(size_t size, size_t *alloc_size, int kmflags);
63 extern void kmem_dump_init(size_t);
64 extern void kmem_dump_begin(void);
65 extern size_t kmem_dump_finish(char *buf, size_t size);
66 extern void *kmem_rezalloc(void *, size_t, size_t, int);
67 
68 #endif	/* _KERNEL */
69 
70 /*
71  * Kernel memory allocator: private interfaces.
72  * These interfaces are still evolving.
73  * Do not use them in unbundled drivers.
74  */
75 
76 /*
77  * Flags for kmem_cache_create()
78  */
79 #define	KMC_NOTOUCH	0x00010000
80 #define	KMC_NODEBUG	0x00020000
81 #define	KMC_NOMAGAZINE	0x00040000
82 #define	KMC_NOHASH	0x00080000
83 #define	KMC_QCACHE	0x00100000
84 #define	KMC_KMEM_ALLOC	0x00200000	/* internal use only */
85 #define	KMC_IDENTIFIER	0x00400000	/* internal use only */
86 #define	KMC_PREFILL	0x00800000
87 
88 struct kmem_cache;		/* cache structure is opaque to kmem clients */
89 
90 typedef struct kmem_cache kmem_cache_t;
91 
92 /* Client response to kmem move callback */
93 typedef enum kmem_cbrc {
94 	KMEM_CBRC_YES,
95 	KMEM_CBRC_NO,
96 	KMEM_CBRC_LATER,
97 	KMEM_CBRC_DONT_NEED,
98 	KMEM_CBRC_DONT_KNOW
99 } kmem_cbrc_t;
100 
101 #if defined(_KERNEL) || defined(_FAKE_KERNEL)
102 
103 /*
104  * Helps clients implementing the move() callback to recognize known objects by
105  * testing a client-designated pointer member. Takes advantage of the fact that
106  * any scribbling to freed memory done by kmem is guaranteed to set one of the
107  * two low order bits.
108  */
109 #define	POINTER_IS_VALID(p)	(!((uintptr_t)(p) & 0x3))
110 #define	POINTER_INVALIDATE(pp)	(*(pp) = (void *)((uintptr_t)(*(pp)) | 0x1))
111 
112 extern int kmem_ready;
113 extern pgcnt_t kmem_reapahead;
114 extern size_t kmem_max_cached;
115 
116 extern void kmem_init(void);
117 extern void kmem_thread_init(void);
118 extern void kmem_mp_init(void);
119 extern void kmem_reap(void);
120 extern void kmem_reap_idspace(void);
121 extern int kmem_debugging(void);
122 extern size_t kmem_avail(void);
123 extern size_t kmem_maxavail(void);
124 
125 extern kmem_cache_t *kmem_cache_create(char *, size_t, size_t,
126 	int (*)(void *, void *, int), void (*)(void *, void *),
127 	void (*)(void *), void *, vmem_t *, int);
128 extern void kmem_cache_set_move(kmem_cache_t *,
129 	kmem_cbrc_t (*)(void *, void *, size_t, void *));
130 extern void kmem_cache_destroy(kmem_cache_t *);
131 extern void *kmem_cache_alloc(kmem_cache_t *, int);
132 extern void kmem_cache_free(kmem_cache_t *, void *);
133 extern uint64_t kmem_cache_stat(kmem_cache_t *, char *);
134 extern boolean_t kmem_cache_reap_active(void);
135 extern void kmem_cache_reap_soon(kmem_cache_t *);
136 extern void kmem_cache_move_notify(kmem_cache_t *, void *);
137 
138 #endif	/* _KERNEL */
139 
140 #ifdef	__cplusplus
141 }
142 #endif
143 
144 #endif	/* _SYS_KMEM_H */
145