lib/libspl/include/umem.h

   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 http://www.opensolaris.org/os/licensing.
  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_NOTOUCH             0x00010000
  61 #define UMC_NODEBUG             0x00020000
  62 #define UMC_NOMAGAZINE          0x00040000
  63 #define UMC_NOHASH              0x00080000
  64
  65 #define UMEM_CACHE_NAMELEN      31
  66
  67 typedef int umem_nofail_callback_t(void);
  68 typedef int umem_constructor_t(void *, void *, int);
  69 typedef void umem_destructor_t(void *, void *);
  70 typedef void umem_reclaim_t(void *);
  71
  72 typedef struct umem_cache {
  73         char                    cache_name[UMEM_CACHE_NAMELEN + 1];
  74         size_t                  cache_bufsize;
  75         size_t                  cache_align;
  76         umem_constructor_t      *cache_constructor;
  77         umem_destructor_t       *cache_destructor;
  78         umem_reclaim_t          *cache_reclaim;
  79         void                    *cache_private;
  80         void                    *cache_arena;
  81         int                     cache_cflags;
  82 } umem_cache_t;
  83
  84 /* Prototypes for functions to provide defaults for umem envvars */
  85 const char *_umem_debug_init(void);
  86 const char *_umem_options_init(void);
  87 const char *_umem_logging_init(void);
  88
  89 static inline void *
  90 umem_alloc(size_t size, int flags)
  91 {
  92         void *ptr = NULL;
  93
  94         do {
  95                 ptr = malloc(size);
  96         } while (ptr == NULL && (flags & UMEM_NOFAIL));
  97
  98         return (ptr);
  99 }
 100
 101 static inline void *
 102 umem_alloc_aligned(size_t size, size_t align, int flags)
 103 {
 104         void *ptr = NULL;
 105         int rc = EINVAL;
 106
 107         do {
 108                 rc = posix_memalign(&ptr, align, size);
 109         } while (rc == ENOMEM && (flags & UMEM_NOFAIL));
 110
 111         if (rc == EINVAL) {
 112                 fprintf(stderr, "%s: invalid memory alignment (%zd)\n",
 113                     __func__, align);
 114                 if (flags & UMEM_NOFAIL)
 115                         abort();
 116                 return (NULL);
 117         }
 118
 119         return (ptr);
 120 }
 121
 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(void *ptr, size_t size __maybe_unused)
 136 {
 137         free(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     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