xref: /freebsd/sys/contrib/openzfs/lib/libspl/include/umem.h (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or https://opensource.org/licenses/CDDL-1.0.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef _LIBSPL_UMEM_H
28 #define	_LIBSPL_UMEM_H
29 
30 /*
31  * XXX: We should use the real portable umem library if it is detected
32  * at configure time.  However, if the library is not available, we can
33  * use a trivial malloc based implementation.  This obviously impacts
34  * performance, but unless you are using a full userspace build of zpool for
35  * something other than ztest, you are likely not going to notice or care.
36  *
37  * https://labs.omniti.com/trac/portableumem
38  */
39 #include <sys/debug.h>
40 
41 #include <stdlib.h>
42 #include <stdio.h>
43 #include <string.h>
44 
45 #ifdef  __cplusplus
46 extern "C" {
47 #endif
48 
49 typedef void vmem_t;
50 
51 /*
52  * Flags for umem_alloc/umem_free
53  */
54 #define	UMEM_DEFAULT		0x0000  /* normal -- may fail */
55 #define	UMEM_NOFAIL		0x0100  /* Never fails */
56 
57 /*
58  * Flags for umem_cache_create()
59  */
60 #define	UMC_NODEBUG		0x00020000
61 
62 #define	UMEM_CACHE_NAMELEN	31
63 
64 typedef int umem_nofail_callback_t(void);
65 typedef int umem_constructor_t(void *, void *, int);
66 typedef void umem_destructor_t(void *, void *);
67 typedef void umem_reclaim_t(void *);
68 
69 typedef struct umem_cache {
70 	char			cache_name[UMEM_CACHE_NAMELEN + 1];
71 	size_t			cache_bufsize;
72 	size_t			cache_align;
73 	umem_constructor_t	*cache_constructor;
74 	umem_destructor_t	*cache_destructor;
75 	umem_reclaim_t		*cache_reclaim;
76 	void			*cache_private;
77 	void			*cache_arena;
78 	int			cache_cflags;
79 } umem_cache_t;
80 
81 /* Prototypes for functions to provide defaults for umem envvars */
82 const char *_umem_debug_init(void);
83 const char *_umem_options_init(void);
84 const char *_umem_logging_init(void);
85 
86 __attribute__((alloc_size(1)))
87 static inline void *
88 umem_alloc(size_t size, int flags)
89 {
90 	void *ptr = NULL;
91 
92 	do {
93 		ptr = malloc(size);
94 	} while (ptr == NULL && (flags & UMEM_NOFAIL));
95 
96 	return (ptr);
97 }
98 
99 __attribute__((alloc_size(1)))
100 static inline void *
101 umem_alloc_aligned(size_t size, size_t align, int flags)
102 {
103 	void *ptr = NULL;
104 	int rc = EINVAL;
105 
106 	do {
107 		rc = posix_memalign(&ptr, align, size);
108 	} while (rc == ENOMEM && (flags & UMEM_NOFAIL));
109 
110 	if (rc == EINVAL) {
111 		fprintf(stderr, "%s: invalid memory alignment (%zd)\n",
112 		    __func__, align);
113 		if (flags & UMEM_NOFAIL)
114 			abort();
115 		return (NULL);
116 	}
117 
118 	return (ptr);
119 }
120 
121 __attribute__((alloc_size(1)))
122 static inline void *
123 umem_zalloc(size_t size, int flags)
124 {
125 	void *ptr = NULL;
126 
127 	ptr = umem_alloc(size, flags);
128 	if (ptr)
129 		memset(ptr, 0, size);
130 
131 	return (ptr);
132 }
133 
134 static inline void
135 umem_free(const void *ptr, size_t size __maybe_unused)
136 {
137 	free((void *)ptr);
138 }
139 
140 static inline void
141 umem_nofail_callback(umem_nofail_callback_t *cb __maybe_unused)
142 {}
143 
144 static inline umem_cache_t *
145 umem_cache_create(
146     const char *name, size_t bufsize, size_t align,
147     umem_constructor_t *constructor,
148     umem_destructor_t *destructor,
149     umem_reclaim_t *reclaim,
150     void *priv, void *vmp, int cflags)
151 {
152 	umem_cache_t *cp;
153 
154 	cp = (umem_cache_t *)umem_alloc(sizeof (umem_cache_t), UMEM_DEFAULT);
155 	if (cp) {
156 		strlcpy(cp->cache_name, name, UMEM_CACHE_NAMELEN);
157 		cp->cache_bufsize = bufsize;
158 		cp->cache_align = align;
159 		cp->cache_constructor = constructor;
160 		cp->cache_destructor = destructor;
161 		cp->cache_reclaim = reclaim;
162 		cp->cache_private = priv;
163 		cp->cache_arena = vmp;
164 		cp->cache_cflags = cflags;
165 	}
166 
167 	return (cp);
168 }
169 
170 static inline void
171 umem_cache_destroy(umem_cache_t *cp)
172 {
173 	umem_free(cp, sizeof (umem_cache_t));
174 }
175 
176 static inline void *
177 umem_cache_alloc(umem_cache_t *cp, int flags)
178 {
179 	void *ptr = NULL;
180 
181 	if (cp->cache_align != 0)
182 		ptr = umem_alloc_aligned(
183 		    cp->cache_bufsize, cp->cache_align, flags);
184 	else
185 		ptr = umem_alloc(cp->cache_bufsize, flags);
186 
187 	if (ptr && cp->cache_constructor)
188 		cp->cache_constructor(ptr, cp->cache_private, UMEM_DEFAULT);
189 
190 	return (ptr);
191 }
192 
193 static inline void
194 umem_cache_free(umem_cache_t *cp, void *ptr)
195 {
196 	if (cp->cache_destructor)
197 		cp->cache_destructor(ptr, cp->cache_private);
198 
199 	umem_free(ptr, cp->cache_bufsize);
200 }
201 
202 static inline void
203 umem_cache_reap_now(umem_cache_t *cp __maybe_unused)
204 {
205 }
206 
207 #ifdef  __cplusplus
208 }
209 #endif
210 
211 #endif
212