xnu-201.tar.gz

[apple/xnu.git] / osfmk / kern / kalloc.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/*
 * HISTORY
 * 
 * Revision 1.1.1.1  1998/09/22 21:05:34  wsanchez
 * Import of Mac OS X kernel (~semeria)
 *
 * Revision 1.1.1.1  1998/03/07 02:25:55  wsanchez
 * Import of OSF Mach kernel (~mburg)
 *
 * Revision 1.2.19.5  1995/02/24  15:20:29  alanl
 *      Lock package cleanup.
 *      [95/02/15            alanl]
 *
 *      Merge with DIPC2_SHARED.
 *      [1995/01/05  15:11:02  alanl]
 *
 * Revision 1.2.28.2  1994/11/10  06:12:50  dwm
 *      mk6 CR764 - s/spinlock/simple_lock/ (name change only)
 *      [1994/11/10  05:28:35  dwm]
 * 
 * Revision 1.2.28.1  1994/11/04  10:07:40  dwm
 *      mk6 CR668 - 1.3b26 merge
 *      * Revision 1.2.2.4  1993/11/08  15:04:18  gm
 *      CR9710: Updated to new zinit() and zone_change() interfaces.
 *      * End1.3merge
 *      [1994/11/04  09:25:48  dwm]
 * 
 * Revision 1.2.19.3  1994/09/23  02:20:52  ezf
 *      change marker to not FREE
 *      [1994/09/22  21:33:57  ezf]
 * 
 * Revision 1.2.19.2  1994/06/14  18:36:36  bolinger
 *      NMK17.2 merge:  Replace simple_lock ops.
 *      [1994/06/14  18:35:17  bolinger]
 * 
 * Revision 1.2.19.1  1994/06/14  17:04:23  bolinger
 *      Merge up to NMK17.2.
 *      [1994/06/14  16:54:19  bolinger]
 * 
 * Revision 1.2.23.3  1994/10/14  12:24:33  sjs
 *      Removed krealloc_spinl routine: the newer locking scheme makes it
 *      obsolete.
 *      [94/10/13            sjs]
 * 
 * Revision 1.2.23.2  1994/08/11  14:42:46  rwd
 *      Post merge cleanup
 *      [94/08/09            rwd]
 * 
 *      Changed zcollectable to use zchange.
 *      [94/08/04            rwd]
 * 
 * Revision 1.2.17.2  1994/07/08  01:58:45  alanl
 *      Change comment to match function name.
 *      [1994/07/08  01:47:59  alanl]
 * 
 * Revision 1.2.17.1  1994/05/26  16:20:38  sjs
 *      Added krealloc_spinl: same as krealloc but uses spin locks.
 *      [94/05/25            sjs]
 * 
 * Revision 1.2.23.1  1994/08/04  02:24:55  mmp
 *      Added krealloc_spinl: same as krealloc but uses spin locks.
 *      [94/05/25            sjs]
 * 
 * Revision 1.2.13.1  1994/02/11  14:27:12  paire
 *      Changed krealloc() to make it work on a MP system. Added a new parameter
 *      which is the simple lock that should be held while modifying the memory
 *      area already initialized.
 *      Change from NMK16.1 [93/09/02            paire]
 * 
 *      Do not set debug for kalloc zones as default. It wastes
 *      to much space.
 *      Change from NMK16.1 [93/08/16            bernadat]
 *      [94/02/07            paire]
 * 
 * Revision 1.2.2.3  1993/07/28  17:15:44  bernard
 *      CR9523 -- Prototypes.
 *      [1993/07/27  20:14:12  bernard]
 * 
 * Revision 1.2.2.2  1993/06/02  23:37:46  jeffc
 *      Added to OSF/1 R1.3 from NMK15.0.
 *      [1993/06/02  21:12:59  jeffc]
 * 
 * Revision 1.2  1992/12/07  21:28:42  robert
 *      integrate any changes below for 14.0 (branch from 13.16 base)
 * 
 *      Joseph Barrera (jsb) at Carnegie-Mellon University 11-Sep-92
 *      Added krealloc. Added kalloc_max_prerounded for quicker choice between
 *      zalloc and kmem_alloc. Renamed MINSIZE to KALLOC_MINSIZE.
 *      [1992/12/06  19:47:16  robert]
 * 
 * Revision 1.1  1992/09/30  02:09:23  robert
 *      Initial revision
 * 
 * $EndLog$
 */
/* CMU_HIST */
/*
 * Revision 2.9  91/05/14  16:43:17  mrt
 *      Correcting copyright
 * 
 * Revision 2.8  91/03/16  14:50:37  rpd
 *      Updated for new kmem_alloc interface.
 *      [91/03/03            rpd]
 * 
 * Revision 2.7  91/02/05  17:27:22  mrt
 *      Changed to new Mach copyright
 *      [91/02/01  16:14:12  mrt]
 * 
 * Revision 2.6  90/06/19  22:59:06  rpd
 *      Made the big kalloc zones collectable.
 *      [90/06/05            rpd]
 * 
 * Revision 2.5  90/06/02  14:54:47  rpd
 *      Added kalloc_max, kalloc_map_size.
 *      [90/03/26  22:06:39  rpd]
 * 
 * Revision 2.4  90/01/11  11:43:13  dbg
 *      De-lint.
 *      [89/12/06            dbg]
 * 
 * Revision 2.3  89/09/08  11:25:51  dbg
 *      MACH_KERNEL: remove non-MACH data types.
 *      [89/07/11            dbg]
 * 
 * Revision 2.2  89/08/31  16:18:59  rwd
 *      First Checkin
 *      [89/08/23  15:41:37  rwd]
 * 
 * Revision 2.6  89/08/02  08:03:28  jsb
 *      Make all kalloc zones 8 MB big. (No more kalloc panics!)
 *      [89/08/01  14:10:17  jsb]
 * 
 * Revision 2.4  89/04/05  13:03:10  rvb
 *      Guarantee a zone max of at least 100 elements or 10 pages
 *      which ever is greater.  Afs (AllocDouble()) puts a great demand
 *      on the 2048 zone and used to blow away.
 *      [89/03/09            rvb]
 * 
 * Revision 2.3  89/02/25  18:04:39  gm0w
 *      Changes for cleanup.
 * 
 * Revision 2.2  89/01/18  02:07:04  jsb
 *      Give each kalloc zone a meaningful name (for panics);
 *      create a zone for each power of 2 between MINSIZE
 *      and PAGE_SIZE, instead of using (obsoleted) NQUEUES.
 *      [89/01/17  10:16:33  jsb]
 * 
 *
 * 13-Feb-88  John Seamons (jks) at NeXT
 *      Updated to use kmem routines instead of vmem routines.
 *
 * 21-Jun-85  Avadis Tevanian (avie) at Carnegie-Mellon University
 *      Created.
 */
/* CMU_ENDHIST */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *      File:   kern/kalloc.c
 *      Author: Avadis Tevanian, Jr.
 *      Date:   1985
 *
 *      General kernel memory allocator.  This allocator is designed
 *      to be used by the kernel to manage dynamic memory fast.
 */

#include <zone_debug.h>

#include <mach/boolean.h>
#include <mach/machine/vm_types.h>
#include <mach/vm_param.h>
#include <kern/misc_protos.h>
#include <kern/zalloc.h>
#include <kern/kalloc.h>
#include <kern/lock.h>
#include <vm/vm_kern.h>
#include <vm/vm_object.h>
#include <vm/vm_map.h>

#ifdef MACH_BSD
zone_t kalloc_zone(vm_size_t);
#endif

vm_map_t kalloc_map;
vm_size_t kalloc_map_size = 16 * 1024 * 1024;
vm_size_t kalloc_max;
vm_size_t kalloc_max_prerounded;

unsigned int kalloc_large_inuse;
vm_size_t    kalloc_large_total;
vm_size_t    kalloc_large_max;

/*
 *      All allocations of size less than kalloc_max are rounded to the
 *      next highest power of 2.  This allocator is built on top of
 *      the zone allocator.  A zone is created for each potential size
 *      that we are willing to get in small blocks.
 *
 *      We assume that kalloc_max is not greater than 64K;
 *      thus 16 is a safe array size for k_zone and k_zone_name.
 *
 *      Note that kalloc_max is somewhat confusingly named.
 *      It represents the first power of two for which no zone exists.
 *      kalloc_max_prerounded is the smallest allocation size, before
 *      rounding, for which no zone exists.
 */

int first_k_zone = -1;
struct zone *k_zone[16];
static char *k_zone_name[16] = {
        "kalloc.1",             "kalloc.2",
        "kalloc.4",             "kalloc.8",
        "kalloc.16",            "kalloc.32",
        "kalloc.64",            "kalloc.128",
        "kalloc.256",           "kalloc.512",
        "kalloc.1024",          "kalloc.2048",
        "kalloc.4096",          "kalloc.8192",
        "kalloc.16384",         "kalloc.32768"
};

/*
 *  Max number of elements per zone.  zinit rounds things up correctly
 *  Doing things this way permits each zone to have a different maximum size
 *  based on need, rather than just guessing; it also
 *  means its patchable in case you're wrong!
 */
unsigned long k_zone_max[16] = {
      1024,             /*      1 Byte  */
      1024,             /*      2 Byte  */
      1024,             /*      4 Byte  */
      1024,             /*      8 Byte  */
      1024,             /*     16 Byte  */
      4096,             /*     32 Byte  */
      4096,             /*     64 Byte  */
      4096,             /*    128 Byte  */
      4096,             /*    256 Byte  */
      1024,             /*    512 Byte  */
      1024,             /*   1024 Byte  */
      1024,             /*   2048 Byte  */
      1024,             /*   4096 Byte  */
      4096,             /*   8192 Byte  */
      64,               /*  16384 Byte  */
      64,               /*  32768 Byte  */
};

/*
 *      Initialize the memory allocator.  This should be called only
 *      once on a system wide basis (i.e. first processor to get here
 *      does the initialization).
 *
 *      This initializes all of the zones.
 */

void
kalloc_init(
        void)
{
        kern_return_t retval;
        vm_offset_t min;
        vm_size_t size;
        register int i;

        retval = kmem_suballoc(kernel_map, &min, kalloc_map_size,
                               FALSE, TRUE, &kalloc_map);
        if (retval != KERN_SUCCESS)
                panic("kalloc_init: kmem_suballoc failed");

        /*
         *      Ensure that zones up to size 8192 bytes exist.
         *      This is desirable because messages are allocated
         *      with kalloc, and messages up through size 8192 are common.
         */

        if (PAGE_SIZE < 16*1024)
                kalloc_max = 16*1024;
        else
                kalloc_max = PAGE_SIZE;
        kalloc_max_prerounded = kalloc_max / 2 + 1;

        /*
         *      Allocate a zone for each size we are going to handle.
         *      We specify non-paged memory.
         */
        for (i = 0, size = 1; size < kalloc_max; i++, size <<= 1) {
                if (size < KALLOC_MINSIZE) {
                        k_zone[i] = 0;
                        continue;
                }
                if (size == KALLOC_MINSIZE) {
                        first_k_zone = i;
                }
                k_zone[i] = zinit(size, k_zone_max[i] * size, size,
                                  k_zone_name[i]);
        }
}

vm_offset_t
kalloc_canblock(
                vm_size_t       size,
                boolean_t       canblock)
{
        register int zindex;
        register vm_size_t allocsize;

        /*
         * If size is too large for a zone, then use kmem_alloc.
         * (We use kmem_alloc instead of kmem_alloc_wired so that
         * krealloc can use kmem_realloc.)
         */

        if (size >= kalloc_max_prerounded) {
                vm_offset_t addr;

                /* kmem_alloc could block so we return if noblock */
                if (!canblock) {
                  return(0);
                }
                if (kmem_alloc(kalloc_map, &addr, size) != KERN_SUCCESS)
                        addr = 0;

                if (addr) {
                        kalloc_large_inuse++;
                        kalloc_large_total += size;

                        if (kalloc_large_total > kalloc_large_max)
                                kalloc_large_max = kalloc_large_total;
                }
                return(addr);
        }

        /* compute the size of the block that we will actually allocate */

        allocsize = KALLOC_MINSIZE;
        zindex = first_k_zone;
        while (allocsize < size) {
                allocsize <<= 1;
                zindex++;
        }

        /* allocate from the appropriate zone */

        assert(allocsize < kalloc_max);
        return(zalloc_canblock(k_zone[zindex], canblock));
}

vm_offset_t
kalloc(
       vm_size_t size)
{
  return( kalloc_canblock(size, TRUE) );
}

vm_offset_t
kalloc_noblock(
               vm_size_t size)
{
  return( kalloc_canblock(size, FALSE) );
}


void
krealloc(
        vm_offset_t     *addrp,
        vm_size_t       old_size,
        vm_size_t       new_size,
        simple_lock_t   lock)
{
        register int zindex;
        register vm_size_t allocsize;
        vm_offset_t naddr;

        /* can only be used for increasing allocation size */

        assert(new_size > old_size);

        /* if old_size is zero, then we are simply allocating */

        if (old_size == 0) {
                simple_unlock(lock);
                naddr = kalloc(new_size);
                simple_lock(lock);
                *addrp = naddr;
                return;
        }

        /* if old block was kmem_alloc'd, then use kmem_realloc if necessary */

        if (old_size >= kalloc_max_prerounded) {
                old_size = round_page(old_size);
                new_size = round_page(new_size);
                if (new_size > old_size) {

                        if (kmem_realloc(kalloc_map, *addrp, old_size, &naddr,
                                         new_size) != KERN_SUCCESS) {
                                panic("krealloc: kmem_realloc");
                                naddr = 0;
                        }

                        simple_lock(lock);
                        *addrp = naddr;

                        /* kmem_realloc() doesn't free old page range. */
                        kmem_free(kalloc_map, *addrp, old_size);

                        kalloc_large_total += (new_size - old_size);

                        if (kalloc_large_total > kalloc_large_max)
                                kalloc_large_max = kalloc_large_total;
                }
                return;
        }

        /* compute the size of the block that we actually allocated */

        allocsize = KALLOC_MINSIZE;
        zindex = first_k_zone;
        while (allocsize < old_size) {
                allocsize <<= 1;
                zindex++;
        }

        /* if new size fits in old block, then return */

        if (new_size <= allocsize) {
                return;
        }

        /* if new size does not fit in zone, kmem_alloc it, else zalloc it */

        simple_unlock(lock);
        if (new_size >= kalloc_max_prerounded) {
                if (kmem_alloc(kalloc_map, &naddr, new_size) != KERN_SUCCESS) {
                        panic("krealloc: kmem_alloc");
                        simple_lock(lock);
                        *addrp = 0;
                        return;
                }
                kalloc_large_inuse++;
                kalloc_large_total += new_size;

                if (kalloc_large_total > kalloc_large_max)
                        kalloc_large_max = kalloc_large_total;
        } else {
                register int new_zindex;

                allocsize <<= 1;
                new_zindex = zindex + 1;
                while (allocsize < new_size) {
                        allocsize <<= 1;
                        new_zindex++;
                }
                naddr = zalloc(k_zone[new_zindex]);
        }
        simple_lock(lock);

        /* copy existing data */

        bcopy((const char *)*addrp, (char *)naddr, old_size);

        /* free old block, and return */

        zfree(k_zone[zindex], *addrp);

        /* set up new address */

        *addrp = naddr;
}


vm_offset_t
kget(
        vm_size_t       size)
{
        register int zindex;
        register vm_size_t allocsize;

        /* size must not be too large for a zone */

        if (size >= kalloc_max_prerounded) {
                /* This will never work, so we might as well panic */
                panic("kget");
        }

        /* compute the size of the block that we will actually allocate */

        allocsize = KALLOC_MINSIZE;
        zindex = first_k_zone;
        while (allocsize < size) {
                allocsize <<= 1;
                zindex++;
        }

        /* allocate from the appropriate zone */

        assert(allocsize < kalloc_max);
        return(zget(k_zone[zindex]));
}

void
kfree(
        vm_offset_t     data,
        vm_size_t       size)
{
        register int zindex;
        register vm_size_t freesize;

        /* if size was too large for a zone, then use kmem_free */

        if (size >= kalloc_max_prerounded) {
                kmem_free(kalloc_map, data, size);

                kalloc_large_total -= size;
                kalloc_large_inuse--;

                return;
        }

        /* compute the size of the block that we actually allocated from */

        freesize = KALLOC_MINSIZE;
        zindex = first_k_zone;
        while (freesize < size) {
                freesize <<= 1;
                zindex++;
        }

        /* free to the appropriate zone */

        assert(freesize < kalloc_max);
        zfree(k_zone[zindex], data);
}

#ifdef MACH_BSD
zone_t
kalloc_zone(
        vm_size_t       size)
{
        register int zindex = 0;
        register vm_size_t allocsize;

        /* compute the size of the block that we will actually allocate */

        allocsize = size;
        if (size <= kalloc_max) {
                allocsize = KALLOC_MINSIZE;
                zindex = first_k_zone;
                while (allocsize < size) {
                        allocsize <<= 1;
                        zindex++;
                }
                return (k_zone[zindex]);
        }
        return (ZONE_NULL);
}
#endif



kalloc_fake_zone_info(int *count, vm_size_t *cur_size, vm_size_t *max_size, vm_size_t *elem_size,
                     vm_size_t *alloc_size, int *collectable, int *exhaustable)
{
        *count      = kalloc_large_inuse;
        *cur_size   = kalloc_large_total;
        *max_size   = kalloc_large_max;
        *elem_size  = kalloc_large_total / kalloc_large_inuse;
        *alloc_size = kalloc_large_total / kalloc_large_inuse;
        *collectable = 0;
        *exhaustable = 0;
}