1 /* 2 * Copyright (c) 2006 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/types.h> 36 #include <sys/mman.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <unistd.h> 41 #include "fsutil.h" 42 #include "memzone.h" 43 44 /* 45 * Efficiently allocate memory that will only be freed in bulk 46 */ 47 void * 48 mzalloc(struct memzone *zone, int bytes) 49 { 50 struct memchunk *chunk; 51 void *ptr; 52 53 if ((chunk = zone->curr) != NULL) { 54 if (bytes > chunk->bytes - zone->index) { 55 chunk->next = zone->list; 56 zone->list = chunk; 57 zone->curr = NULL; 58 chunk = NULL; 59 } 60 } 61 if (chunk == NULL) { 62 chunk = malloc(sizeof(*chunk)); 63 if (chunk == NULL) 64 return(NULL); 65 bzero(chunk, sizeof(*chunk)); 66 chunk->base = mmap(NULL, MEMZONE_CHUNK, PROT_READ|PROT_WRITE, 67 MAP_ANON|MAP_PRIVATE, -1, 0); 68 if (chunk->base == MAP_FAILED) { 69 free(chunk); 70 return(NULL); 71 } 72 chunk->bytes = MEMZONE_CHUNK; 73 zone->curr = chunk; 74 zone->index = 0; 75 } 76 if (bytes > chunk->bytes) 77 pfatal("allocation to large for mzalloc!"); 78 ptr = chunk->base + zone->index; 79 zone->index += (bytes + 7) & ~7; 80 return(ptr); 81 } 82 83 /* 84 * Free memory in bulk 85 */ 86 void 87 mzpurge(struct memzone *zone) 88 { 89 struct memchunk *chunk; 90 91 if ((chunk = zone->curr) != NULL) { 92 chunk->next = zone->list; 93 zone->list = chunk; 94 zone->curr = NULL; 95 } 96 while ((chunk = zone->list) != NULL) { 97 zone->list = chunk->next; 98 munmap(chunk->base, chunk->bytes); 99 free(chunk); 100 } 101 } 102 103