/* * Copyright (c) 2002, Jeffrey Roberson * 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 unmodified, 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. * * $FreeBSD$ * */ /* * uma.h - External definitions for the Universal Memory Allocator * * Jeff Roberson */ #ifndef VM_UMA_H #define VM_UMA_H #include /* For NULL */ #include /* For M_* */ /* User visable parameters */ #define UMA_SMALLEST_UNIT (PAGE_SIZE / 256) /* Smallest item allocated */ /* Types and type defs */ struct uma_zone; /* Opaque type used as a handle to the zone */ typedef struct uma_zone * uma_zone_t; /* * Item constructor * * Arguments: * item A pointer to the memory which has been allocated. * arg The arg field passed to uma_zalloc_arg * size The size of the allocated item * * Returns: * Nothing * * Discussion: * The constructor is called just before the memory is returned * to the user. It may block if neccisary. */ typedef void (*uma_ctor)(void *mem, int size, void *arg); /* * Item destructor * * Arguments: * item A pointer to the memory which has been allocated. * size The size of the item being destructed. * arg Argument passed through uma_zfree_arg * * Returns: * Nothing * * Discussion: * The destructor may perform operations that differ from those performed * by the initializer, but it must leave the object in the same state. * This IS type stable storage. This is called after EVERY zfree call. */ typedef void (*uma_dtor)(void *mem, int size, void *arg); /* * Item initializer * * Arguments: * item A pointer to the memory which has been allocated. * size The size of the item being initialized. * * Returns: * Nothing * * Discussion: * The initializer is called when the memory is cached in the uma zone. * this should be the same state that the destructor leaves the object in. */ typedef void (*uma_init)(void *mem, int size); /* * Item discard function * * Arguments: * item A pointer to memory which has been 'freed' but has not left the * zone's cache. * size The size of the item being discarded. * * Returns: * Nothing * * Discussion: * This routine is called when memory leaves a zone and is returned to the * system for other uses. It is the counter part to the init function. */ typedef void (*uma_fini)(void *mem, int size); /* * What's the difference between initializing and constructing? * * The item is initialized when it is cached, and this is the state that the * object should be in when returned to the allocator. The purpose of this is * to remove some code which would otherwise be called on each allocation by * utilizing a known, stable state. This differs from the constructor which * will be called on EVERY allocation. * * For example, in the initializer you may want to initialize embeded locks, * NULL list pointers, set up initial states, magic numbers, etc. This way if * the object is held in the allocator and re-used it won't be neccisary to * re-initialize it. * * The constructor may be used to lock a data structure, link it on to lists, * bump reference counts or total counts of outstanding structures, etc. * */ /* Function proto types */ /* * Create a new uma zone * * Arguments: * name The text name of the zone for debugging and stats, this memory * should not be freed until the zone has been deallocated. * size The size of the object that is being created. * ctor The constructor that is called when the object is allocated * dtor The destructor that is called when the object is freed. * init An initializer that sets up the initial state of the memory. * fini A discard function that undoes initialization done by init. * ctor/dtor/init/fini may all be null, see notes above. * align A bitmask that corisponds to the requested alignment * eg 4 would be 0x3 * flags A set of parameters that control the behavior of the zone * * Returns: * A pointer to a structure which is intended to be opaque to users of * the interface. The value may be null if the wait flag is not set. */ uma_zone_t uma_zcreate(char *name, int size, uma_ctor ctor, uma_dtor dtor, uma_init uminit, uma_fini fini, int align, u_int16_t flags); /* Definitions for uma_zcreate flags */ #define UMA_ZONE_PAGEABLE 0x0001 /* Return items not fully backed by physical memory XXX Not yet */ #define UMA_ZONE_ZINIT 0x0002 /* Initialize with zeros */ #define UMA_ZONE_STATIC 0x0004 /* Staticly sized zone */ #define UMA_ZONE_OFFPAGE 0x0008 /* Force the slab structure allocation off of the real memory */ #define UMA_ZONE_MALLOC 0x0010 /* For use by malloc(9) only! */ #define UMA_ZONE_NOFREE 0x0020 /* Do not free slabs of this type! */ #define UMA_ZONE_MTXCLASS 0x0040 /* Create a new lock class */ /* Definitions for align */ #define UMA_ALIGN_PTR (sizeof(void *) - 1) /* Alignment fit for ptr */ #define UMA_ALIGN_LONG (sizeof(long) - 1) /* "" long */ #define UMA_ALIGN_INT (sizeof(int) - 1) /* "" int */ #define UMA_ALIGN_SHORT (sizeof(short) - 1) /* "" short */ #define UMA_ALIGN_CHAR (sizeof(char) - 1) /* "" char */ #define UMA_ALIGN_CACHE (16 - 1) /* Cache line size align */ /* * Destroys an empty uma zone. If the zone is not empty uma complains loudly. * * Arguments: * zone The zone we want to destroy. * */ void uma_zdestroy(uma_zone_t zone); /* * Allocates an item out of a zone * * Arguments: * zone The zone we are allocating from * arg This data is passed to the ctor function * flags See sys/malloc.h for available flags. * * Returns: * A non null pointer to an initialized element from the zone is * garanteed if the wait flag is M_WAITOK, otherwise a null pointer may be * returned if the zone is empty or the ctor failed. */ void *uma_zalloc_arg(uma_zone_t zone, void *arg, int flags); /* * Allocates an item out of a zone without supplying an argument * * This is just a wrapper for uma_zalloc_arg for convenience. * */ static __inline void *uma_zalloc(uma_zone_t zone, int flags); static __inline void * uma_zalloc(uma_zone_t zone, int flags) { return uma_zalloc_arg(zone, NULL, flags); } /* * Frees an item back into the specified zone. * * Arguments: * zone The zone the item was originally allocated out of. * item The memory to be freed. * arg Argument passed to the destructor * * Returns: * Nothing. */ void uma_zfree_arg(uma_zone_t zone, void *item, void *arg); /* * Frees an item back to a zone without supplying an argument * * This is just a wrapper for uma_zfree_arg for convenience. * */ static __inline void uma_zfree(uma_zone_t zone, void *item); static __inline void uma_zfree(uma_zone_t zone, void *item) { return uma_zfree_arg(zone, item, NULL); } /* * XXX The rest of the prototypes in this header are h0h0 magic for the VM. * If you think you need to use it for a normal zone you're probably incorrect. */ /* * Backend page supplier routines * * Arguments: * zone The zone that is requesting pages * size The number of bytes being requested * pflag Flags for these memory pages, see below. * wait Indicates our willingness to block. * * Returns: * A pointer to the alloced memory or NULL on failure. */ typedef void *(*uma_alloc)(uma_zone_t zone, int size, u_int8_t *pflag, int wait); /* * Backend page free routines * * Arguments: * item A pointer to the previously allocated pages * size The original size of the allocation * pflag The flags for the slab. See UMA_SLAB_* below * * Returns: * None */ typedef void (*uma_free)(void *item, int size, u_int8_t pflag); /* * Sets up the uma allocator. (Called by vm_mem_init) * * Arguments: * bootmem A pointer to memory used to bootstrap the system. * * Returns: * Nothing * * Discussion: * This memory is used for zones which allocate things before the * backend page supplier can give us pages. It should be * UMA_SLAB_SIZE * UMA_BOOT_PAGES bytes. (see uma_int.h) * */ void uma_startup(void *bootmem); /* * Finishes starting up the allocator. This should * be called when kva is ready for normal allocs. * * Arguments: * hash An area of memory that will become the malloc hash * elems The number of elements in this array * * Returns: * Nothing * * Discussion: * uma_startup2 is called by kmeminit() to prepare the malloc * hash bucket, and enable use of uma for malloc ops. */ void uma_startup2(void *hash, u_long elems); /* * Reclaims unused memory for all zones * * Arguments: * None * Returns: * None * * This should only be called by the page out daemon. */ void uma_reclaim(void); /* * Switches the backing object of a zone * * Arguments: * zone The zone to update * obj The obj to use for future allocations * size The size of the object to allocate * * Returns: * 0 if kva space can not be allocated * 1 if successful * * Discussion: * A NULL object can be used and uma will allocate one for you. Setting * the size will limit the amount of memory allocated to this zone. * */ struct vm_object; int uma_zone_set_obj(uma_zone_t zone, struct vm_object *obj, int size); /* * Sets a high limit on the number of items allowed in a zone * * Arguments: * zone The zone to limit * * Returns: * Nothing */ void uma_zone_set_max(uma_zone_t zone, int nitems); /* * Replaces the standard page_alloc or obj_alloc functions for this zone * * Arguments: * zone The zone whos back end allocator is being changed. * allocf A pointer to the allocation function * * Returns: * Nothing * * Discussion: * This could be used to implement pageable allocation, or perhaps * even DMA allocators if used in conjunction with the OFFPAGE * zone flag. */ void uma_zone_set_allocf(uma_zone_t zone, uma_alloc allocf); /* * Used for freeing memory provided by the allocf above * * Arguments: * zone The zone that intends to use this free routine. * freef The page freeing routine. * * Returns: * Nothing */ void uma_zone_set_freef(uma_zone_t zone, uma_free freef); /* * These flags are setable in the allocf and visable in the freef. */ #define UMA_SLAB_BOOT 0x01 /* Slab alloced from boot pages */ #define UMA_SLAB_KMEM 0x02 /* Slab alloced from kmem_map */ #define UMA_SLAB_KMAP 0x04 /* Slab alloced from kernel_map */ #define UMA_SLAB_PRIV 0x08 /* Slab alloced from priv allocator */ #define UMA_SLAB_OFFP 0x10 /* Slab is managed separately */ #define UMA_SLAB_MALLOC 0x20 /* Slab is a large malloc slab */ /* 0x40 and 0x80 are available */ /* * Used to pre-fill a zone with some number of items * * Arguments: * zone The zone to fill * itemcnt The number of items to reserve * * Returns: * Nothing * * NOTE: This is blocking and should only be done at startup */ void uma_prealloc(uma_zone_t zone, int itemcnt); #endif