kern_malloc.c revision 1.143.4.1
1 /* $NetBSD: kern_malloc.c,v 1.143.4.1 2015/04/06 15:18:20 skrll Exp $ */ 2 3 /* 4 * Copyright (c) 1987, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 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 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)kern_malloc.c 8.4 (Berkeley) 5/20/95 32 */ 33 34 /* 35 * Copyright (c) 1996 Christopher G. Demetriou. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)kern_malloc.c 8.4 (Berkeley) 5/20/95 66 */ 67 68 /* 69 * Wrapper interface for obsolete malloc(9). 70 */ 71 72 #include <sys/cdefs.h> 73 __KERNEL_RCSID(0, "$NetBSD: kern_malloc.c,v 1.143.4.1 2015/04/06 15:18:20 skrll Exp $"); 74 75 #include <sys/param.h> 76 #include <sys/malloc.h> 77 #include <sys/kmem.h> 78 79 /* 80 * Built-in malloc types. Note: ought to be removed. 81 */ 82 MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory"); 83 MALLOC_DEFINE(M_DMAMAP, "DMA map", "bus_dma(9) structures"); 84 MALLOC_DEFINE(M_FREE, "free", "should be on free list"); 85 MALLOC_DEFINE(M_TEMP, "temp", "misc. temporary data buffers"); 86 MALLOC_DEFINE(M_RTABLE, "routetbl", "routing tables"); 87 MALLOC_DEFINE(M_FTABLE, "fragtbl", "fragment reassembly header"); 88 MALLOC_DEFINE(M_UFSMNT, "UFS mount", "UFS mount structure"); 89 MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 90 MALLOC_DEFINE(M_MRTABLE, "mrt", "multicast routing tables"); 91 92 /* 93 * Header contains total size, including the header itself. 94 */ 95 struct malloc_header { 96 size_t mh_size; 97 } __aligned(ALIGNBYTES + 1); 98 99 void * 100 kern_malloc(unsigned long size, int flags) 101 { 102 const int kmflags = (flags & M_NOWAIT) ? KM_NOSLEEP : KM_SLEEP; 103 size_t allocsize, hdroffset; 104 struct malloc_header *mh; 105 void *p; 106 107 if (size >= PAGE_SIZE) { 108 allocsize = PAGE_SIZE + size; /* for page alignment */ 109 hdroffset = PAGE_SIZE - sizeof(struct malloc_header); 110 } else { 111 allocsize = sizeof(struct malloc_header) + size; 112 hdroffset = 0; 113 } 114 115 p = kmem_intr_alloc(allocsize, kmflags); 116 if (p == NULL) 117 return NULL; 118 119 if ((flags & M_ZERO) != 0) { 120 memset(p, 0, allocsize); 121 } 122 mh = (void *)((char *)p + hdroffset); 123 mh->mh_size = allocsize - hdroffset; 124 125 return mh + 1; 126 } 127 128 void 129 kern_free(void *addr) 130 { 131 struct malloc_header *mh; 132 133 mh = addr; 134 mh--; 135 136 if (mh->mh_size >= PAGE_SIZE + sizeof(struct malloc_header)) 137 kmem_intr_free((char *)addr - PAGE_SIZE, 138 mh->mh_size + PAGE_SIZE - sizeof(struct malloc_header)); 139 else 140 kmem_intr_free(mh, mh->mh_size); 141 } 142 143 void * 144 kern_realloc(void *curaddr, unsigned long newsize, int flags) 145 { 146 struct malloc_header *mh; 147 unsigned long cursize; 148 void *newaddr; 149 150 /* 151 * realloc() with a NULL pointer is the same as malloc(). 152 */ 153 if (curaddr == NULL) 154 return malloc(newsize, ksp, flags); 155 156 /* 157 * realloc() with zero size is the same as free(). 158 */ 159 if (newsize == 0) { 160 free(curaddr, ksp); 161 return NULL; 162 } 163 164 if ((flags & M_NOWAIT) == 0) { 165 ASSERT_SLEEPABLE(); 166 } 167 168 mh = curaddr; 169 mh--; 170 171 cursize = mh->mh_size - sizeof(struct malloc_header); 172 173 /* 174 * If we already actually have as much as they want, we're done. 175 */ 176 if (newsize <= cursize) 177 return curaddr; 178 179 /* 180 * Can't satisfy the allocation with the existing block. 181 * Allocate a new one and copy the data. 182 */ 183 newaddr = malloc(newsize, ksp, flags); 184 if (__predict_false(newaddr == NULL)) { 185 /* 186 * malloc() failed, because flags included M_NOWAIT. 187 * Return NULL to indicate that failure. The old 188 * pointer is still valid. 189 */ 190 return NULL; 191 } 192 memcpy(newaddr, curaddr, cursize); 193 194 /* 195 * We were successful: free the old allocation and return 196 * the new one. 197 */ 198 free(curaddr, ksp); 199 return newaddr; 200 } 201
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