1 /*-
2 * Copyright (c) 1987, 1993
3 * The Regents of the University of California.
4 * Copyright (c) 2005, 2009 Robert N. M. Watson
5 * 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 * 4. 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 * @(#)malloc.h 8.5 (Berkeley) 5/3/95
32 * $FreeBSD: stable/10/sys/sys/malloc.h 328276 2018-01-23 04:37:31Z kp $
33 */
34
35 #ifndef _SYS_MALLOC_H_
36 #define _SYS_MALLOC_H_
37
38 #include <sys/param.h>
39 #include <sys/queue.h>
40 #include <sys/_lock.h>
41 #include <sys/_mutex.h>
42 #include <machine/_limits.h>
43
44 #define MINALLOCSIZE UMA_SMALLEST_UNIT
45
46 /*
47 * flags to malloc.
48 */
49 #define M_NOWAIT 0x0001 /* do not block */
50 #define M_WAITOK 0x0002 /* ok to block */
51 #define M_ZERO 0x0100 /* bzero the allocation */
52 #define M_NOVM 0x0200 /* don't ask VM for pages */
53 #define M_USE_RESERVE 0x0400 /* can alloc out of reserve memory */
54 #define M_NODUMP 0x0800 /* don't dump pages in this allocation */
55 #define M_FIRSTFIT 0x1000 /* Only for vmem, fast fit. */
56 #define M_BESTFIT 0x2000 /* Only for vmem, low fragmentation. */
57
58 #define M_MAGIC 877983977 /* time when first defined :-) */
59
60 /*
61 * Two malloc type structures are present: malloc_type, which is used by a
62 * type owner to declare the type, and malloc_type_internal, which holds
63 * malloc-owned statistics and other ABI-sensitive fields, such as the set of
64 * malloc statistics indexed by the compile-time MAXCPU constant.
65 * Applications should avoid introducing dependence on the allocator private
66 * data layout and size.
67 *
68 * The malloc_type ks_next field is protected by malloc_mtx. Other fields in
69 * malloc_type are static after initialization so unsynchronized.
70 *
71 * Statistics in malloc_type_stats are written only when holding a critical
72 * section and running on the CPU associated with the index into the stat
73 * array, but read lock-free resulting in possible (minor) races, which the
74 * monitoring app should take into account.
75 */
76 struct malloc_type_stats {
77 uint64_t mts_memalloced; /* Bytes allocated on CPU. */
78 uint64_t mts_memfreed; /* Bytes freed on CPU. */
79 uint64_t mts_numallocs; /* Number of allocates on CPU. */
80 uint64_t mts_numfrees; /* number of frees on CPU. */
81 uint64_t mts_size; /* Bitmask of sizes allocated on CPU. */
82 uint64_t _mts_reserved1; /* Reserved field. */
83 uint64_t _mts_reserved2; /* Reserved field. */
84 uint64_t _mts_reserved3; /* Reserved field. */
85 };
86
87 /*
88 * Index definitions for the mti_probes[] array.
89 */
90 #define DTMALLOC_PROBE_MALLOC 0
91 #define DTMALLOC_PROBE_FREE 1
92 #define DTMALLOC_PROBE_MAX 2
93
94 struct malloc_type_internal {
95 uint32_t mti_probes[DTMALLOC_PROBE_MAX];
96 /* DTrace probe ID array. */
97 u_char mti_zone;
98 struct malloc_type_stats mti_stats[MAXCPU];
99 };
100
101 /*
102 * Public data structure describing a malloc type. Private data is hung off
103 * of ks_handle to avoid encoding internal malloc(9) data structures in
104 * modules, which will statically allocate struct malloc_type.
105 */
106 struct malloc_type {
107 struct malloc_type *ks_next; /* Next in global chain. */
108 u_long ks_magic; /* Detect programmer error. */
109 const char *ks_shortdesc; /* Printable type name. */
110 void *ks_handle; /* Priv. data, was lo_class. */
111 };
112
113 /*
114 * Statistics structure headers for user space. The kern.malloc sysctl
115 * exposes a structure stream consisting of a stream header, then a series of
116 * malloc type headers and statistics structures (quantity maxcpus). For
117 * convenience, the kernel will provide the current value of maxcpus at the
118 * head of the stream.
119 */
120 #define MALLOC_TYPE_STREAM_VERSION 0x00000001
121 struct malloc_type_stream_header {
122 uint32_t mtsh_version; /* Stream format version. */
123 uint32_t mtsh_maxcpus; /* Value of MAXCPU for stream. */
124 uint32_t mtsh_count; /* Number of records. */
125 uint32_t _mtsh_pad; /* Pad/reserved field. */
126 };
127
128 #define MALLOC_MAX_NAME 32
129 struct malloc_type_header {
130 char mth_name[MALLOC_MAX_NAME];
131 };
132
133 #ifdef _KERNEL
134 #define MALLOC_DEFINE(type, shortdesc, longdesc) \
135 struct malloc_type type[1] = { \
136 { NULL, M_MAGIC, shortdesc, NULL } \
137 }; \
138 SYSINIT(type##_init, SI_SUB_KMEM, SI_ORDER_SECOND, malloc_init, \
139 type); \
140 SYSUNINIT(type##_uninit, SI_SUB_KMEM, SI_ORDER_ANY, \
141 malloc_uninit, type)
142
143 #define MALLOC_DECLARE(type) \
144 extern struct malloc_type type[1]
145
146 MALLOC_DECLARE(M_CACHE);
147 MALLOC_DECLARE(M_DEVBUF);
148 MALLOC_DECLARE(M_TEMP);
149
150 MALLOC_DECLARE(M_IP6OPT); /* for INET6 */
151 MALLOC_DECLARE(M_IP6NDP); /* for INET6 */
152
153 /*
154 * Deprecated macro versions of not-quite-malloc() and free().
155 */
156 #define MALLOC(space, cast, size, type, flags) \
157 ((space) = (cast)malloc((u_long)(size), (type), (flags)))
158 #define FREE(addr, type) free((addr), (type))
159
160 /*
161 * XXX this should be declared in <sys/uio.h>, but that tends to fail
162 * because <sys/uio.h> is included in a header before the source file
163 * has a chance to include <sys/malloc.h> to get MALLOC_DECLARE() defined.
164 */
165 MALLOC_DECLARE(M_IOV);
166
167 extern struct mtx malloc_mtx;
168
169 /*
170 * Function type used when iterating over the list of malloc types.
171 */
172 typedef void malloc_type_list_func_t(struct malloc_type *, void *);
173
174 void contigfree(void *addr, unsigned long size, struct malloc_type *type);
175 void *contigmalloc(unsigned long size, struct malloc_type *type, int flags,
176 vm_paddr_t low, vm_paddr_t high, unsigned long alignment,
177 vm_paddr_t boundary) __malloc_like;
178 void free(void *addr, struct malloc_type *type);
179 void *malloc(unsigned long size, struct malloc_type *type, int flags) __malloc_like;
180 void *mallocarray(size_t nmemb, size_t size, struct malloc_type *type,
181 int flags) __malloc_like __result_use_check;
182 void malloc_init(void *);
183 int malloc_last_fail(void);
184 void malloc_type_allocated(struct malloc_type *type, unsigned long size);
185 void malloc_type_freed(struct malloc_type *type, unsigned long size);
186 void malloc_type_list(malloc_type_list_func_t *, void *);
187 void malloc_uninit(void *);
188 void *realloc(void *addr, unsigned long size, struct malloc_type *type,
189 int flags);
190 void *reallocf(void *addr, unsigned long size, struct malloc_type *type,
191 int flags);
192
193 struct malloc_type *malloc_desc2type(const char *desc);
194
195 /*
196 * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
197 * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
198 */
199 #define MUL_NO_OVERFLOW (1UL << (sizeof(size_t) * 8 / 2))
200 static inline bool
WOULD_OVERFLOW(size_t nmemb,size_t size)201 WOULD_OVERFLOW(size_t nmemb, size_t size)
202 {
203
204 return ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
205 nmemb > 0 && __SIZE_T_MAX / nmemb < size);
206 }
207 #undef MUL_NO_OVERFLOW
208 #endif /* _KERNEL */
209
210 #endif /* !_SYS_MALLOC_H_ */
211