/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1987, 1993 * The Regents of the University of California. * Copyright (c) 2005, 2009 Robert N. M. Watson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef _SYS_MALLOC_H_ #define _SYS_MALLOC_H_ #ifndef _STANDALONE #include <sys/param.h> #ifdef _KERNEL #include <sys/systm.h> #endif #include <sys/queue.h> #include <sys/_lock.h> #include <sys/_mutex.h> #include <machine/_limits.h> #define MINALLOCSIZE UMA_SMALLEST_UNIT /* * Flags to memory allocation functions. */ #define M_NOWAIT 0x0001 /* do not block */ #define M_WAITOK 0x0002 /* ok to block */ #define M_NORECLAIM 0x0080 /* do not reclaim after failure */ #define M_ZERO 0x0100 /* bzero the allocation */ #define M_NOVM 0x0200 /* don't ask VM for pages */ #define M_USE_RESERVE 0x0400 /* can alloc out of reserve memory */ #define M_NODUMP 0x0800 /* don't dump pages in this allocation */ #define M_FIRSTFIT 0x1000 /* only for vmem, fast fit */ #define M_BESTFIT 0x2000 /* only for vmem, low fragmentation */ #define M_EXEC 0x4000 /* allocate executable space */ #define M_NEXTFIT 0x8000 /* only for vmem, follow cursor */ #define M_NEVERFREED 0x10000 /* chunk will never get freed */ #define M_UNPROTECTED 0x20000 /* alloc out of unprotected memory */ #define M_VERSION 2024073001 /* * Two malloc type structures are present: malloc_type, which is used by a * type owner to declare the type, and malloc_type_internal, which holds * malloc-owned statistics and other ABI-sensitive fields, such as the set of * malloc statistics indexed by the compile-time MAXCPU constant. * Applications should avoid introducing dependence on the allocator private * data layout and size. * * The malloc_type ks_next field is protected by malloc_mtx. Other fields in * malloc_type are static after initialization so unsynchronized. * * Statistics in malloc_type_stats are written only when holding a critical * section and running on the CPU associated with the index into the stat * array, but read lock-free resulting in possible (minor) races, which the * monitoring app should take into account. */ struct malloc_type_stats { uint64_t mts_memalloced; /* Bytes allocated on CPU. */ uint64_t mts_memfreed; /* Bytes freed on CPU. */ uint64_t mts_numallocs; /* Number of allocates on CPU. */ uint64_t mts_numfrees; /* number of frees on CPU. */ uint64_t mts_size; /* Bitmask of sizes allocated on CPU. */ uint64_t _mts_reserved1; /* Reserved field. */ uint64_t _mts_reserved2; /* Reserved field. */ uint64_t _mts_reserved3; /* Reserved field. */ }; _Static_assert(sizeof(struct malloc_type_stats) == 64, "allocations come from pcpu_zone_64"); /* * Index definitions for the mti_probes[] array. */ #define DTMALLOC_PROBE_MALLOC 0 #define DTMALLOC_PROBE_FREE 1 #define DTMALLOC_PROBE_MAX 2 struct malloc_type_internal { uint32_t mti_probes[DTMALLOC_PROBE_MAX]; /* DTrace probe ID array. */ u_char mti_zone; struct malloc_type_stats *mti_stats; u_long mti_spare[8]; }; /* * Public data structure describing a malloc type. */ struct malloc_type { struct malloc_type *ks_next; /* Next in global chain. */ u_long ks_version; /* Detect programmer error. */ const char *ks_shortdesc; /* Printable type name. */ struct malloc_type_internal ks_mti; }; /* * Statistics structure headers for user space. The kern.malloc sysctl * exposes a structure stream consisting of a stream header, then a series of * malloc type headers and statistics structures (quantity maxcpus). For * convenience, the kernel will provide the current value of maxcpus at the * head of the stream. */ #define MALLOC_TYPE_STREAM_VERSION 0x00000001 struct malloc_type_stream_header { uint32_t mtsh_version; /* Stream format version. */ uint32_t mtsh_maxcpus; /* Value of MAXCPU for stream. */ uint32_t mtsh_count; /* Number of records. */ uint32_t _mtsh_pad; /* Pad/reserved field. */ }; #define MALLOC_MAX_NAME 32 struct malloc_type_header { char mth_name[MALLOC_MAX_NAME]; }; #ifdef _KERNEL #define MALLOC_DEFINE(type, shortdesc, longdesc) \ struct malloc_type type[1] = { \ { \ .ks_next = NULL, \ .ks_version = M_VERSION, \ .ks_shortdesc = shortdesc, \ } \ }; \ SYSINIT(type##_init, SI_SUB_KMEM, SI_ORDER_THIRD, malloc_init, \ type); \ SYSUNINIT(type##_uninit, SI_SUB_KMEM, SI_ORDER_ANY, \ malloc_uninit, type) #define MALLOC_DECLARE(type) \ extern struct malloc_type type[1] MALLOC_DECLARE(M_CACHE); MALLOC_DECLARE(M_DEVBUF); MALLOC_DECLARE(M_PARGS); MALLOC_DECLARE(M_SESSION); MALLOC_DECLARE(M_SUBPROC); MALLOC_DECLARE(M_TEMP); /* * XXX this should be declared in <sys/uio.h>, but that tends to fail * because <sys/uio.h> is included in a header before the source file * has a chance to include <sys/malloc.h> to get MALLOC_DECLARE() defined. */ MALLOC_DECLARE(M_IOV); struct domainset; extern struct mtx malloc_mtx; /* * Function type used when iterating over the list of malloc types. */ typedef void malloc_type_list_func_t(struct malloc_type *, void *); /* contigfree(9) is deprecated. */ void contigfree(void *addr, unsigned long, struct malloc_type *type); void *contigmalloc(unsigned long size, struct malloc_type *type, int flags, vm_paddr_t low, vm_paddr_t high, unsigned long alignment, vm_paddr_t boundary) __malloc_like __result_use_check __alloc_size(1) __alloc_align(6); void *contigmalloc_domainset(unsigned long size, struct malloc_type *type, struct domainset *ds, int flags, vm_paddr_t low, vm_paddr_t high, unsigned long alignment, vm_paddr_t boundary) __malloc_like __result_use_check __alloc_size(1) __alloc_align(7); void free(void *addr, struct malloc_type *type); void zfree(void *addr, struct malloc_type *type); void *malloc(size_t size, struct malloc_type *type, int flags) __malloc_like __result_use_check __alloc_size(1); /* * Try to optimize malloc(..., ..., M_ZERO) allocations by doing zeroing in * place if the size is known at compilation time. * * Passing the flag down requires malloc to blindly zero the entire object. * In practice a lot of the zeroing can be avoided if most of the object * gets explicitly initialized after the allocation. Letting the compiler * zero in place gives it the opportunity to take advantage of this state. * * Note that the operation is only applicable if both flags and size are * known at compilation time. If M_ZERO is passed but M_WAITOK is not, the * allocation can fail and a NULL check is needed. However, if M_WAITOK is * passed we know the allocation must succeed and the check can be elided. * * _malloc_item = malloc(_size, type, (flags) &~ M_ZERO); * if (((flags) & M_WAITOK) != 0 || _malloc_item != NULL) * bzero(_malloc_item, _size); * * If the flag is set, the compiler knows the left side is always true, * therefore the entire statement is true and the callsite is: * * _malloc_item = malloc(_size, type, (flags) &~ M_ZERO); * bzero(_malloc_item, _size); * * If the flag is not set, the compiler knows the left size is always false * and the NULL check is needed, therefore the callsite is: * * _malloc_item = malloc(_size, type, (flags) &~ M_ZERO); * if (_malloc_item != NULL) * bzero(_malloc_item, _size); * * The implementation is a macro because of what appears to be a clang 6 bug: * an inline function variant ended up being compiled to a mere malloc call * regardless of argument. gcc generates expected code (like the above). */ #define malloc(size, type, flags) ({ \ void *_malloc_item; \ size_t _size = (size); \ if (__builtin_constant_p(size) && __builtin_constant_p(flags) &&\ ((flags) & M_ZERO) != 0) { \ _malloc_item = malloc(_size, type, (flags) &~ M_ZERO); \ if (((flags) & M_WAITOK) != 0 || \ __predict_true(_malloc_item != NULL)) \ memset(_malloc_item, 0, _size); \ } else { \ _malloc_item = malloc(_size, type, flags); \ } \ _malloc_item; \ }) void *malloc_domainset(size_t size, struct malloc_type *type, struct domainset *ds, int flags) __malloc_like __result_use_check __alloc_size(1); void *mallocarray(size_t nmemb, size_t size, struct malloc_type *type, int flags) __malloc_like __result_use_check __alloc_size2(1, 2); void *mallocarray_domainset(size_t nmemb, size_t size, struct malloc_type *type, struct domainset *ds, int flags) __malloc_like __result_use_check __alloc_size2(1, 2); void *malloc_exec(size_t size, struct malloc_type *type, int flags) __malloc_like __result_use_check __alloc_size(1); void *malloc_domainset_exec(size_t size, struct malloc_type *type, struct domainset *ds, int flags) __malloc_like __result_use_check __alloc_size(1); void malloc_init(void *); void malloc_type_allocated(struct malloc_type *type, unsigned long size); void malloc_type_freed(struct malloc_type *type, unsigned long size); void malloc_type_list(malloc_type_list_func_t *, void *); void malloc_uninit(void *); size_t malloc_size(size_t); size_t malloc_usable_size(const void *); void *realloc(void *addr, size_t size, struct malloc_type *type, int flags) __result_use_check __alloc_size(2); void *reallocf(void *addr, size_t size, struct malloc_type *type, int flags) __result_use_check __alloc_size(2); void *malloc_aligned(size_t size, size_t align, struct malloc_type *type, int flags) __malloc_like __result_use_check __alloc_size(1); void *malloc_domainset_aligned(size_t size, size_t align, struct malloc_type *mtp, struct domainset *ds, int flags) __malloc_like __result_use_check __alloc_size(1); struct malloc_type *malloc_desc2type(const char *desc); /* * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW */ #define MUL_NO_OVERFLOW (1UL << (sizeof(size_t) * 8 / 2)) static inline bool WOULD_OVERFLOW(size_t nmemb, size_t size) { return ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) && nmemb > 0 && __SIZE_T_MAX / nmemb < size); } #undef MUL_NO_OVERFLOW #endif /* _KERNEL */ #else /* * The native stand malloc / free interface we're mapping to */ extern void Free(void *p, const char *file, int line); extern void *Malloc(size_t bytes, const char *file, int line); /* * Minimal standalone malloc implementation / environment. None of the * flags mean anything and there's no need declare malloc types. * Define the simple alloc / free routines in terms of Malloc and * Free. None of the kernel features that this stuff disables are needed. */ #define M_WAITOK 1 #define M_ZERO 0 #define M_NOWAIT 2 #define MALLOC_DECLARE(x) #define kmem_zalloc(size, flags) ({ \ void *p = Malloc((size), __FILE__, __LINE__); \ if (p == NULL && (flags & M_WAITOK) != 0) \ panic("Could not malloc %zd bytes with M_WAITOK from %s line %d", \ (size_t)size, __FILE__, __LINE__); \ p; \ }) #define kmem_free(p, size) Free(p, __FILE__, __LINE__) /* * ZFS mem.h define that's the OpenZFS porting layer way of saying * M_WAITOK. Given the above, it will also be a nop. */ #define KM_SLEEP M_WAITOK #define KM_NOSLEEP M_NOWAIT #endif /* _STANDALONE */ #endif /* !_SYS_MALLOC_H_ */
