Remove a check that is always false.
[dragonfly.git] / sbin / fsck / memzone.c
CommitLineData
f2c50142
MD
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 * $DragonFly: src/sbin/fsck/memzone.c,v 1.1 2006/10/12 04:04:03 dillon Exp $
35 */
36
37#include <sys/types.h>
38#include <sys/mman.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <unistd.h>
42#include "memzone.h"
43
44/*
45 * Efficiently allocate memory that will only be freed in bulk
46 */
47void *
48mzalloc(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 */
86void *
87mzpurge(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