kern_malloc.c

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/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1987, 1991, 1993
 *      The Regents of the University of California.
 * Copyright (c) 2005-2009 Robert N. M. Watson
 * Copyright (c) 2008 Otto Moerbeek <otto@drijf.net> (mallocarray)
 * 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.
 *
 *      @(#)kern_malloc.c       8.3 (Berkeley) 1/4/94
 */
 
/*
 * Kernel malloc(9) implementation -- general purpose kernel memory allocator
 * based on memory types.  Back end is implemented using the UMA(9) zone
 * allocator.  A set of fixed-size buckets are used for smaller allocations,
 * and a special UMA allocation interface is used for larger allocations.
 * Callers declare memory types, and statistics are maintained independently
 * for each memory type.  Statistics are maintained per-CPU for performance
 * reasons.  See malloc(9) and comments in malloc.h for a detailed
 * description.
 */
 
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
 
#include "opt_ddb.h"
#include "opt_vm.h"
 
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/asan.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/msan.h>
#include <sys/mutex.h>
#include <sys/vmmeter.h>
#include <sys/proc.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/smp.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/vmem.h>
#ifdef EPOCH_TRACE
#include <sys/epoch.h>
#endif
 
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_domainset.h>
#include <vm/vm_pageout.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
#include <vm/vm_map.h>
#include <vm/vm_page.h>
#include <vm/vm_phys.h>
#include <vm/vm_pagequeue.h>
#include <vm/uma.h>
#include <vm/uma_int.h>
#include <vm/uma_dbg.h>
 
#ifdef DEBUG_MEMGUARD
#include <vm/memguard.h>
#endif
#ifdef DEBUG_REDZONE
#include <vm/redzone.h>
#endif
 
#if defined(INVARIANTS) && defined(__i386__)
#include <machine/cpu.h>
#endif
 
#include <ddb/ddb.h>
 
#ifdef KDTRACE_HOOKS
#include <sys/dtrace_bsd.h>
 
bool    __read_frequently                       dtrace_malloc_enabled;
dtrace_malloc_probe_func_t __read_mostly        dtrace_malloc_probe;
#endif
 
#if defined(INVARIANTS) || defined(MALLOC_MAKE_FAILURES) ||             \
    defined(DEBUG_MEMGUARD) || defined(DEBUG_REDZONE)
#define MALLOC_DEBUG    1
#endif
 
#if defined(KASAN) || defined(DEBUG_REDZONE)
#define DEBUG_REDZONE_ARG_DEF   , unsigned long osize
#define DEBUG_REDZONE_ARG       , osize
#else
#define DEBUG_REDZONE_ARG_DEF
#define DEBUG_REDZONE_ARG
#endif
 
/*
 * When realloc() is called, if the new size is sufficiently smaller than
 * the old size, realloc() will allocate a new, smaller block to avoid
 * wasting memory. 'Sufficiently smaller' is defined as: newsize <=
 * oldsize / 2^n, where REALLOC_FRACTION defines the value of 'n'.
 */
#ifndef REALLOC_FRACTION
#define REALLOC_FRACTION        1       /* new block if <= half the size */
#endif
 
/*
 * Centrally define some common malloc types.
 */
MALLOC_DEFINE(M_CACHE, "cache", "Various Dynamically allocated caches");
MALLOC_DEFINE(M_DEVBUF, "devbuf", "device driver memory");
MALLOC_DEFINE(M_TEMP, "temp", "misc temporary data buffers");
 
static struct malloc_type *kmemstatistics;
static int kmemcount;
 
#define KMEM_ZSHIFT     4
#define KMEM_ZBASE      16
#define KMEM_ZMASK      (KMEM_ZBASE - 1)
 
#define KMEM_ZMAX       65536
#define KMEM_ZSIZE      (KMEM_ZMAX >> KMEM_ZSHIFT)
static uint8_t kmemsize[KMEM_ZSIZE + 1];
 
#ifndef MALLOC_DEBUG_MAXZONES
#define MALLOC_DEBUG_MAXZONES   1
#endif
static int numzones = MALLOC_DEBUG_MAXZONES;
 
/*
 * Small malloc(9) memory allocations are allocated from a set of UMA buckets
 * of various sizes.
 *
 * Warning: the layout of the struct is duplicated in libmemstat for KVM support.
 *
 * XXX: The comment here used to read "These won't be powers of two for
 * long."  It's possible that a significant amount of wasted memory could be
 * recovered by tuning the sizes of these buckets.
 */
struct {
        int kz_size;
        const char *kz_name;
        uma_zone_t kz_zone[MALLOC_DEBUG_MAXZONES];
} kmemzones[] = {
        {16, "malloc-16", },
        {32, "malloc-32", },
        {64, "malloc-64", },
        {128, "malloc-128", },
        {256, "malloc-256", },
        {384, "malloc-384", },
        {512, "malloc-512", },
        {1024, "malloc-1024", },
        {2048, "malloc-2048", },
        {4096, "malloc-4096", },
        {8192, "malloc-8192", },
        {16384, "malloc-16384", },
        {32768, "malloc-32768", },
        {65536, "malloc-65536", },
        {0, NULL},
};
 
u_long vm_kmem_size;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_size, CTLFLAG_RDTUN, &vm_kmem_size, 0,
    "Size of kernel memory");
 
static u_long kmem_zmax = KMEM_ZMAX;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_zmax, CTLFLAG_RDTUN, &kmem_zmax, 0,
    "Maximum allocation size that malloc(9) would use UMA as backend");
 
static u_long vm_kmem_size_min;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_min, CTLFLAG_RDTUN, &vm_kmem_size_min, 0,
    "Minimum size of kernel memory");
 
static u_long vm_kmem_size_max;
SYSCTL_ULONG(_vm, OID_AUTO, kmem_size_max, CTLFLAG_RDTUN, &vm_kmem_size_max, 0,
    "Maximum size of kernel memory");
 
static u_int vm_kmem_size_scale;
SYSCTL_UINT(_vm, OID_AUTO, kmem_size_scale, CTLFLAG_RDTUN, &vm_kmem_size_scale, 0,
    "Scale factor for kernel memory size");
 
static int sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS);
SYSCTL_PROC(_vm, OID_AUTO, kmem_map_size,
    CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0,
    sysctl_kmem_map_size, "LU", "Current kmem allocation size");
 
static int sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS);
SYSCTL_PROC(_vm, OID_AUTO, kmem_map_free,
    CTLFLAG_RD | CTLTYPE_ULONG | CTLFLAG_MPSAFE, NULL, 0,
    sysctl_kmem_map_free, "LU", "Free space in kmem");
 
static SYSCTL_NODE(_vm, OID_AUTO, malloc, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
    "Malloc information");
 
static u_int vm_malloc_zone_count = nitems(kmemzones);
SYSCTL_UINT(_vm_malloc, OID_AUTO, zone_count,
    CTLFLAG_RD, &vm_malloc_zone_count, 0,
    "Number of malloc zones");
 
static int sysctl_vm_malloc_zone_sizes(SYSCTL_HANDLER_ARGS);
SYSCTL_PROC(_vm_malloc, OID_AUTO, zone_sizes,
    CTLFLAG_RD | CTLTYPE_OPAQUE | CTLFLAG_MPSAFE, NULL, 0,
    sysctl_vm_malloc_zone_sizes, "S", "Zone sizes used by malloc");
 
/*
 * The malloc_mtx protects the kmemstatistics linked list.
 */
struct mtx malloc_mtx;
 
static int sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS);
 
#if defined(MALLOC_MAKE_FAILURES) || (MALLOC_DEBUG_MAXZONES > 1)
static SYSCTL_NODE(_debug, OID_AUTO, malloc, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
    "Kernel malloc debugging options");
#endif
 
/*
 * malloc(9) fault injection -- cause malloc failures every (n) mallocs when
 * the caller specifies M_NOWAIT.  If set to 0, no failures are caused.
 */
#ifdef MALLOC_MAKE_FAILURES
static int malloc_failure_rate;
static int malloc_nowait_count;
static int malloc_failure_count;
SYSCTL_INT(_debug_malloc, OID_AUTO, failure_rate, CTLFLAG_RWTUN,
    &malloc_failure_rate, 0, "Every (n) mallocs with M_NOWAIT will fail");
SYSCTL_INT(_debug_malloc, OID_AUTO, failure_count, CTLFLAG_RD,
    &malloc_failure_count, 0, "Number of imposed M_NOWAIT malloc failures");
#endif
 
static int
sysctl_kmem_map_size(SYSCTL_HANDLER_ARGS)
{
        u_long size;
 
        size = uma_size();
        return (sysctl_handle_long(oidp, &size, 0, req));
}
 
static int
sysctl_kmem_map_free(SYSCTL_HANDLER_ARGS)
{
        u_long size, limit;
 
        /* The sysctl is unsigned, implement as a saturation value. */
        size = uma_size();
        limit = uma_limit();
        if (size > limit)
                size = 0;
        else
                size = limit - size;
        return (sysctl_handle_long(oidp, &size, 0, req));
}
 
static int
sysctl_vm_malloc_zone_sizes(SYSCTL_HANDLER_ARGS)
{
        int sizes[nitems(kmemzones)];
        int i;
 
        for (i = 0; i < nitems(kmemzones); i++) {
                sizes[i] = kmemzones[i].kz_size;
        }
 
        return (SYSCTL_OUT(req, &sizes, sizeof(sizes)));
}
 
/*
 * malloc(9) uma zone separation -- sub-page buffer overruns in one
 * malloc type will affect only a subset of other malloc types.
 */
#if MALLOC_DEBUG_MAXZONES > 1
static void
tunable_set_numzones(void)
{
 
        TUNABLE_INT_FETCH("debug.malloc.numzones",
            &numzones);
 
        /* Sanity check the number of malloc uma zones. */
        if (numzones <= 0)
                numzones = 1;
        if (numzones > MALLOC_DEBUG_MAXZONES)
                numzones = MALLOC_DEBUG_MAXZONES;
}
SYSINIT(numzones, SI_SUB_TUNABLES, SI_ORDER_ANY, tunable_set_numzones, NULL);
SYSCTL_INT(_debug_malloc, OID_AUTO, numzones, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
    &numzones, 0, "Number of malloc uma subzones");
 
/*
 * Any number that changes regularly is an okay choice for the
 * offset.  Build numbers are pretty good of you have them.
 */
static u_int zone_offset = __FreeBSD_version;
TUNABLE_INT("debug.malloc.zone_offset", &zone_offset);
SYSCTL_UINT(_debug_malloc, OID_AUTO, zone_offset, CTLFLAG_RDTUN,
    &zone_offset, 0, "Separate malloc types by examining the "
    "Nth character in the malloc type short description.");
 
static void
mtp_set_subzone(struct malloc_type *mtp)
{
        struct malloc_type_internal *mtip;
        const char *desc;
        size_t len;
        u_int val;
 
        mtip = &mtp->ks_mti;
        desc = mtp->ks_shortdesc;
        if (desc == NULL || (len = strlen(desc)) == 0)
                val = 0;
        else
                val = desc[zone_offset % len];
        mtip->mti_zone = (val % numzones);
}
 
static inline u_int
mtp_get_subzone(struct malloc_type *mtp)
{
        struct malloc_type_internal *mtip;
 
        mtip = &mtp->ks_mti;
 
        KASSERT(mtip->mti_zone < numzones,
            ("mti_zone %u out of range %d",
            mtip->mti_zone, numzones));
        return (mtip->mti_zone);
}
#elif MALLOC_DEBUG_MAXZONES == 0
#error "MALLOC_DEBUG_MAXZONES must be positive."
#else
static void
mtp_set_subzone(struct malloc_type *mtp)
{
        struct malloc_type_internal *mtip;
 
        mtip = &mtp->ks_mti;
        mtip->mti_zone = 0;
}
 
static inline u_int
mtp_get_subzone(struct malloc_type *mtp)
{
 
        return (0);
}
#endif /* MALLOC_DEBUG_MAXZONES > 1 */
 
/*
 * An allocation has succeeded -- update malloc type statistics for the
 * amount of bucket size.  Occurs within a critical section so that the
 * thread isn't preempted and doesn't migrate while updating per-PCU
 * statistics.
 */
static void
malloc_type_zone_allocated(struct malloc_type *mtp, unsigned long size,
    int zindx)
{
        struct malloc_type_internal *mtip;
        struct malloc_type_stats *mtsp;
 
        critical_enter();
        mtip = &mtp->ks_mti;
        mtsp = zpcpu_get(mtip->mti_stats);
        if (size > 0) {
                mtsp->mts_memalloced += size;
                mtsp->mts_numallocs++;
        }
        if (zindx != -1)
                mtsp->mts_size |= 1 << zindx;
 
#ifdef KDTRACE_HOOKS
        if (__predict_false(dtrace_malloc_enabled)) {
                uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_MALLOC];
                if (probe_id != 0)
                        (dtrace_malloc_probe)(probe_id,
                            (uintptr_t) mtp, (uintptr_t) mtip,
                            (uintptr_t) mtsp, size, zindx);
        }
#endif
 
        critical_exit();
}
 
void
malloc_type_allocated(struct malloc_type *mtp, unsigned long size)
{
 
        if (size > 0)
                malloc_type_zone_allocated(mtp, size, -1);
}
 
/*
 * A free operation has occurred -- update malloc type statistics for the
 * amount of the bucket size.  Occurs within a critical section so that the
 * thread isn't preempted and doesn't migrate while updating per-CPU
 * statistics.
 */
void
malloc_type_freed(struct malloc_type *mtp, unsigned long size)
{
        struct malloc_type_internal *mtip;
        struct malloc_type_stats *mtsp;
 
        critical_enter();
        mtip = &mtp->ks_mti;
        mtsp = zpcpu_get(mtip->mti_stats);
        mtsp->mts_memfreed += size;
        mtsp->mts_numfrees++;
 
#ifdef KDTRACE_HOOKS
        if (__predict_false(dtrace_malloc_enabled)) {
                uint32_t probe_id = mtip->mti_probes[DTMALLOC_PROBE_FREE];
                if (probe_id != 0)
                        (dtrace_malloc_probe)(probe_id,
                            (uintptr_t) mtp, (uintptr_t) mtip,
                            (uintptr_t) mtsp, size, 0);
        }
#endif
 
        critical_exit();
}
 
/*
 *      contigmalloc:
 *
 *      Allocate a block of physically contiguous memory.
 *
 *      If M_NOWAIT is set, this routine will not block and return NULL if
 *      the allocation fails.
 */
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)
{
        void *ret;
 
        ret = (void *)kmem_alloc_contig(size, flags, low, high, alignment,
            boundary, VM_MEMATTR_DEFAULT);
        if (ret != NULL)
                malloc_type_allocated(type, round_page(size));
        return (ret);
}
 
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)
{
        void *ret;
 
        ret = (void *)kmem_alloc_contig_domainset(ds, size, flags, low, high,
            alignment, boundary, VM_MEMATTR_DEFAULT);
        if (ret != NULL)
                malloc_type_allocated(type, round_page(size));
        return (ret);
}
 
/*
 *      contigfree:
 *
 *      Free a block of memory allocated by contigmalloc.
 *
 *      This routine may not block.
 */
void
contigfree(void *addr, unsigned long size, struct malloc_type *type)
{
 
        kmem_free((vm_offset_t)addr, size);
        malloc_type_freed(type, round_page(size));
}
 
#ifdef MALLOC_DEBUG
static int
malloc_dbg(caddr_t *vap, size_t *sizep, struct malloc_type *mtp,
    int flags)
{
#ifdef INVARIANTS
        int indx;
 
        KASSERT(mtp->ks_version == M_VERSION, ("malloc: bad malloc type version"));
        /*
         * Check that exactly one of M_WAITOK or M_NOWAIT is specified.
         */
        indx = flags & (M_WAITOK | M_NOWAIT);
        if (indx != M_NOWAIT && indx != M_WAITOK) {
                static  struct timeval lasterr;
                static  int curerr, once;
                if (once == 0 && ppsratecheck(&lasterr, &curerr, 1)) {
                        printf("Bad malloc flags: %x\n", indx);
                        kdb_backtrace();
                        flags |= M_WAITOK;
                        once++;
                }
        }
#endif
#ifdef MALLOC_MAKE_FAILURES
        if ((flags & M_NOWAIT) && (malloc_failure_rate != 0)) {
                atomic_add_int(&malloc_nowait_count, 1);
                if ((malloc_nowait_count % malloc_failure_rate) == 0) {
                        atomic_add_int(&malloc_failure_count, 1);
                        *vap = NULL;
                        return (EJUSTRETURN);
                }
        }
#endif
        if (flags & M_WAITOK) {
                KASSERT(curthread->td_intr_nesting_level == 0,
                   ("malloc(M_WAITOK) in interrupt context"));
                if (__predict_false(!THREAD_CAN_SLEEP())) {
#ifdef EPOCH_TRACE
                        epoch_trace_list(curthread);
#endif
                        KASSERT(0,
                            ("malloc(M_WAITOK) with sleeping prohibited"));
                }
        }
        KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
            ("malloc: called with spinlock or critical section held"));
 
#ifdef DEBUG_MEMGUARD
        if (memguard_cmp_mtp(mtp, *sizep)) {
                *vap = memguard_alloc(*sizep, flags);
                if (*vap != NULL)
                        return (EJUSTRETURN);
                /* This is unfortunate but should not be fatal. */
        }
#endif
 
#ifdef DEBUG_REDZONE
        *sizep = redzone_size_ntor(*sizep);
#endif
 
        return (0);
}
#endif
 
/*
 * Handle large allocations and frees by using kmem_malloc directly.
 */
static inline bool
malloc_large_slab(uma_slab_t slab)
{
        uintptr_t va;
 
        va = (uintptr_t)slab;
        return ((va & 1) != 0);
}
 
static inline size_t
malloc_large_size(uma_slab_t slab)
{
        uintptr_t va;
 
        va = (uintptr_t)slab;
        return (va >> 1);
}
 
static caddr_t __noinline
malloc_large(size_t size, struct malloc_type *mtp, struct domainset *policy,
    int flags DEBUG_REDZONE_ARG_DEF)
{
        vm_offset_t kva;
        caddr_t va;
 
        size = roundup(size, PAGE_SIZE);
        kva = kmem_malloc_domainset(policy, size, flags);
        if (kva != 0) {
                /* The low bit is unused for slab pointers. */
                vsetzoneslab(kva, NULL, (void *)((size << 1) | 1));
                uma_total_inc(size);
        }
        va = (caddr_t)kva;
        malloc_type_allocated(mtp, va == NULL ? 0 : size);
        if (__predict_false(va == NULL)) {
                KASSERT((flags & M_WAITOK) == 0,
                    ("malloc(M_WAITOK) returned NULL"));
        } else {
#ifdef DEBUG_REDZONE
                va = redzone_setup(va, osize);
#endif
                kasan_mark((void *)va, osize, size, KASAN_MALLOC_REDZONE);
        }
        return (va);
}
 
static void
free_large(void *addr, size_t size)
{
 
        kmem_free((vm_offset_t)addr, size);
        uma_total_dec(size);
}
 
/*
 *      malloc:
 *
 *      Allocate a block of memory.
 *
 *      If M_NOWAIT is set, this routine will not block and return NULL if
 *      the allocation fails.
 */
void *
(malloc)(size_t size, struct malloc_type *mtp, int flags)
{
        int indx;
        caddr_t va;
        uma_zone_t zone;
#if defined(DEBUG_REDZONE) || defined(KASAN)
        unsigned long osize = size;
#endif
 
        MPASS((flags & M_EXEC) == 0);
 
#ifdef MALLOC_DEBUG
        va = NULL;
        if (malloc_dbg(&va, &size, mtp, flags) != 0)
                return (va);
#endif
 
        if (__predict_false(size > kmem_zmax))
                return (malloc_large(size, mtp, DOMAINSET_RR(), flags
                    DEBUG_REDZONE_ARG));
 
        if (size & KMEM_ZMASK)
                size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
        indx = kmemsize[size >> KMEM_ZSHIFT];
        zone = kmemzones[indx].kz_zone[mtp_get_subzone(mtp)];
        va = uma_zalloc(zone, flags);
        if (va != NULL) {
                size = zone->uz_size;
                if ((flags & M_ZERO) == 0) {
                        kmsan_mark(va, size, KMSAN_STATE_UNINIT);
                        kmsan_orig(va, size, KMSAN_TYPE_MALLOC, KMSAN_RET_ADDR);
                }
        }
        malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx);
        if (__predict_false(va == NULL)) {
                KASSERT((flags & M_WAITOK) == 0,
                    ("malloc(M_WAITOK) returned NULL"));
        }
#ifdef DEBUG_REDZONE
        if (va != NULL)
                va = redzone_setup(va, osize);
#endif
#ifdef KASAN
        if (va != NULL)
                kasan_mark((void *)va, osize, size, KASAN_MALLOC_REDZONE);
#endif
        return ((void *) va);
}
 
static void *
malloc_domain(size_t *sizep, int *indxp, struct malloc_type *mtp, int domain,
    int flags)
{
        uma_zone_t zone;
        caddr_t va;
        size_t size;
        int indx;
 
        size = *sizep;
        KASSERT(size <= kmem_zmax && (flags & M_EXEC) == 0,
            ("malloc_domain: Called with bad flag / size combination."));
        if (size & KMEM_ZMASK)
                size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
        indx = kmemsize[size >> KMEM_ZSHIFT];
        zone = kmemzones[indx].kz_zone[mtp_get_subzone(mtp)];
        va = uma_zalloc_domain(zone, NULL, domain, flags);
        if (va != NULL)
                *sizep = zone->uz_size;
        *indxp = indx;
        return ((void *)va);
}
 
void *
malloc_domainset(size_t size, struct malloc_type *mtp, struct domainset *ds,
    int flags)
{
        struct vm_domainset_iter di;
        caddr_t va;
        int domain;
        int indx;
#if defined(KASAN) || defined(DEBUG_REDZONE)
        unsigned long osize = size;
#endif
 
        MPASS((flags & M_EXEC) == 0);
 
#ifdef MALLOC_DEBUG
        va = NULL;
        if (malloc_dbg(&va, &size, mtp, flags) != 0)
                return (va);
#endif
 
        if (__predict_false(size > kmem_zmax))
                return (malloc_large(size, mtp, DOMAINSET_RR(), flags
                    DEBUG_REDZONE_ARG));
 
        vm_domainset_iter_policy_init(&di, ds, &domain, &flags);
        do {
                va = malloc_domain(&size, &indx, mtp, domain, flags);
        } while (va == NULL && vm_domainset_iter_policy(&di, &domain) == 0);
        malloc_type_zone_allocated(mtp, va == NULL ? 0 : size, indx);
        if (__predict_false(va == NULL)) {
                KASSERT((flags & M_WAITOK) == 0,
                    ("malloc(M_WAITOK) returned NULL"));
        }
#ifdef DEBUG_REDZONE
        if (va != NULL)
                va = redzone_setup(va, osize);
#endif
#ifdef KASAN
        if (va != NULL)
                kasan_mark((void *)va, osize, size, KASAN_MALLOC_REDZONE);
#endif
#ifdef KMSAN
        if ((flags & M_ZERO) == 0) {
                kmsan_mark(va, size, KMSAN_STATE_UNINIT);
                kmsan_orig(va, size, KMSAN_TYPE_MALLOC, KMSAN_RET_ADDR);
        }
#endif
        return (va);
}
 
/*
 * Allocate an executable area.
 */
void *
malloc_exec(size_t size, struct malloc_type *mtp, int flags)
{
 
        return (malloc_domainset_exec(size, mtp, DOMAINSET_RR(), flags));
}
 
void *
malloc_domainset_exec(size_t size, struct malloc_type *mtp, struct domainset *ds,
    int flags)
{
#if defined(DEBUG_REDZONE) || defined(KASAN)
        unsigned long osize = size;
#endif
#ifdef MALLOC_DEBUG
        caddr_t va;
#endif
 
        flags |= M_EXEC;
 
#ifdef MALLOC_DEBUG
        va = NULL;
        if (malloc_dbg(&va, &size, mtp, flags) != 0)
                return (va);
#endif
 
        return (malloc_large(size, mtp, ds, flags DEBUG_REDZONE_ARG));
}
 
void *
malloc_aligned(size_t size, size_t align, struct malloc_type *type, int flags)
{
        return (malloc_domainset_aligned(size, align, type, DOMAINSET_RR(),
            flags));
}
 
void *
malloc_domainset_aligned(size_t size, size_t align,
    struct malloc_type *mtp, struct domainset *ds, int flags)
{
        void *res;
        size_t asize;
 
        KASSERT(powerof2(align),
            ("malloc_domainset_aligned: wrong align %#zx size %#zx",
            align, size));
        KASSERT(align <= PAGE_SIZE,
            ("malloc_domainset_aligned: align %#zx (size %#zx) too large",
            align, size));
 
        /*
         * Round the allocation size up to the next power of 2,
         * because we can only guarantee alignment for
         * power-of-2-sized allocations.  Further increase the
         * allocation size to align if the rounded size is less than
         * align, since malloc zones provide alignment equal to their
         * size.
         */
        if (size == 0)
                size = 1;
        asize = size <= align ? align : 1UL << flsl(size - 1);
 
        res = malloc_domainset(asize, mtp, ds, flags);
        KASSERT(res == NULL || ((uintptr_t)res & (align - 1)) == 0,
            ("malloc_domainset_aligned: result not aligned %p size %#zx "
            "allocsize %#zx align %#zx", res, size, asize, align));
        return (res);
}
 
void *
mallocarray(size_t nmemb, size_t size, struct malloc_type *type, int flags)
{
 
        if (WOULD_OVERFLOW(nmemb, size))
                panic("mallocarray: %zu * %zu overflowed", nmemb, size);
 
        return (malloc(size * nmemb, type, flags));
}
 
void *
mallocarray_domainset(size_t nmemb, size_t size, struct malloc_type *type,
    struct domainset *ds, int flags)
{
 
        if (WOULD_OVERFLOW(nmemb, size))
                panic("mallocarray_domainset: %zu * %zu overflowed", nmemb, size);
 
        return (malloc_domainset(size * nmemb, type, ds, flags));
}
 
#if defined(INVARIANTS) && !defined(KASAN)
static void
free_save_type(void *addr, struct malloc_type *mtp, u_long size)
{
        struct malloc_type **mtpp = addr;
 
        /*
         * Cache a pointer to the malloc_type that most recently freed
         * this memory here.  This way we know who is most likely to
         * have stepped on it later.
         *
         * This code assumes that size is a multiple of 8 bytes for
         * 64 bit machines
         */
        mtpp = (struct malloc_type **) ((unsigned long)mtpp & ~UMA_ALIGN_PTR);
        mtpp += (size - sizeof(struct malloc_type *)) /
            sizeof(struct malloc_type *);
        *mtpp = mtp;
}
#endif
 
#ifdef MALLOC_DEBUG
static int
free_dbg(void **addrp, struct malloc_type *mtp)
{
        void *addr;
 
        addr = *addrp;
        KASSERT(mtp->ks_version == M_VERSION, ("free: bad malloc type version"));
        KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
            ("free: called with spinlock or critical section held"));
 
        /* free(NULL, ...) does nothing */
        if (addr == NULL)
                return (EJUSTRETURN);
 
#ifdef DEBUG_MEMGUARD
        if (is_memguard_addr(addr)) {
                memguard_free(addr);
                return (EJUSTRETURN);
        }
#endif
 
#ifdef DEBUG_REDZONE
        redzone_check(addr);
        *addrp = redzone_addr_ntor(addr);
#endif
 
        return (0);
}
#endif
 
/*
 *      free:
 *
 *      Free a block of memory allocated by malloc.
 *
 *      This routine may not block.
 */
void
free(void *addr, struct malloc_type *mtp)
{
        uma_zone_t zone;
        uma_slab_t slab;
        u_long size;
 
#ifdef MALLOC_DEBUG
        if (free_dbg(&addr, mtp) != 0)
                return;
#endif
        /* free(NULL, ...) does nothing */
        if (addr == NULL)
                return;
 
        vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab);
        if (slab == NULL)
                panic("free: address %p(%p) has not been allocated.\n",
                    addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
 
        if (__predict_true(!malloc_large_slab(slab))) {
                size = zone->uz_size;
#if defined(INVARIANTS) && !defined(KASAN)
                free_save_type(addr, mtp, size);
#endif
                uma_zfree_arg(zone, addr, slab);
        } else {
                size = malloc_large_size(slab);
                free_large(addr, size);
        }
        malloc_type_freed(mtp, size);
}
 
/*
 *      zfree:
 *
 *      Zero then free a block of memory allocated by malloc.
 *
 *      This routine may not block.
 */
void
zfree(void *addr, struct malloc_type *mtp)
{
        uma_zone_t zone;
        uma_slab_t slab;
        u_long size;
 
#ifdef MALLOC_DEBUG
        if (free_dbg(&addr, mtp) != 0)
                return;
#endif
        /* free(NULL, ...) does nothing */
        if (addr == NULL)
                return;
 
        vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab);
        if (slab == NULL)
                panic("free: address %p(%p) has not been allocated.\n",
                    addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
 
        if (__predict_true(!malloc_large_slab(slab))) {
                size = zone->uz_size;
#if defined(INVARIANTS) && !defined(KASAN)
                free_save_type(addr, mtp, size);
#endif
                kasan_mark(addr, size, size, 0);
                explicit_bzero(addr, size);
                uma_zfree_arg(zone, addr, slab);
        } else {
                size = malloc_large_size(slab);
                kasan_mark(addr, size, size, 0);
                explicit_bzero(addr, size);
                free_large(addr, size);
        }
        malloc_type_freed(mtp, size);
}
 
/*
 *      realloc: change the size of a memory block
 */
void *
realloc(void *addr, size_t size, struct malloc_type *mtp, int flags)
{
        uma_zone_t zone;
        uma_slab_t slab;
        unsigned long alloc;
        void *newaddr;
 
        KASSERT(mtp->ks_version == M_VERSION,
            ("realloc: bad malloc type version"));
        KASSERT(curthread->td_critnest == 0 || SCHEDULER_STOPPED(),
            ("realloc: called with spinlock or critical section held"));
 
        /* realloc(NULL, ...) is equivalent to malloc(...) */
        if (addr == NULL)
                return (malloc(size, mtp, flags));
 
        /*
         * XXX: Should report free of old memory and alloc of new memory to
         * per-CPU stats.
         */
 
#ifdef DEBUG_MEMGUARD
        if (is_memguard_addr(addr))
                return (memguard_realloc(addr, size, mtp, flags));
#endif
 
#ifdef DEBUG_REDZONE
        slab = NULL;
        zone = NULL;
        alloc = redzone_get_size(addr);
#else
        vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab);
 
        /* Sanity check */
        KASSERT(slab != NULL,
            ("realloc: address %p out of range", (void *)addr));
 
        /* Get the size of the original block */
        if (!malloc_large_slab(slab))
                alloc = zone->uz_size;
        else
                alloc = malloc_large_size(slab);
 
        /* Reuse the original block if appropriate */
        if (size <= alloc &&
            (size > (alloc >> REALLOC_FRACTION) || alloc == MINALLOCSIZE)) {
                kasan_mark((void *)addr, size, alloc, KASAN_MALLOC_REDZONE);
                return (addr);
        }
#endif /* !DEBUG_REDZONE */
 
        /* Allocate a new, bigger (or smaller) block */
        if ((newaddr = malloc(size, mtp, flags)) == NULL)
                return (NULL);
 
        /*
         * Copy over original contents.  For KASAN, the redzone must be marked
         * valid before performing the copy.
         */
        kasan_mark(addr, alloc, alloc, 0);
        bcopy(addr, newaddr, min(size, alloc));
        free(addr, mtp);
        return (newaddr);
}
 
/*
 *      reallocf: same as realloc() but free memory on failure.
 */
void *
reallocf(void *addr, size_t size, struct malloc_type *mtp, int flags)
{
        void *mem;
 
        if ((mem = realloc(addr, size, mtp, flags)) == NULL)
                free(addr, mtp);
        return (mem);
}
 
/*
 *      malloc_size: returns the number of bytes allocated for a request of the
 *                   specified size
 */
size_t
malloc_size(size_t size)
{
        int indx;
 
        if (size > kmem_zmax)
                return (0);
        if (size & KMEM_ZMASK)
                size = (size & ~KMEM_ZMASK) + KMEM_ZBASE;
        indx = kmemsize[size >> KMEM_ZSHIFT];
        return (kmemzones[indx].kz_size);
}
 
/*
 *      malloc_usable_size: returns the usable size of the allocation.
 */
size_t
malloc_usable_size(const void *addr)
{
#ifndef DEBUG_REDZONE
        uma_zone_t zone;
        uma_slab_t slab;
#endif
        u_long size;
 
        if (addr == NULL)
                return (0);
 
#ifdef DEBUG_MEMGUARD
        if (is_memguard_addr(__DECONST(void *, addr)))
                return (memguard_get_req_size(addr));
#endif
 
#ifdef DEBUG_REDZONE
        size = redzone_get_size(__DECONST(void *, addr));
#else
        vtozoneslab((vm_offset_t)addr & (~UMA_SLAB_MASK), &zone, &slab);
        if (slab == NULL)
                panic("malloc_usable_size: address %p(%p) is not allocated.\n",
                    addr, (void *)((u_long)addr & (~UMA_SLAB_MASK)));
 
        if (!malloc_large_slab(slab))
                size = zone->uz_size;
        else
                size = malloc_large_size(slab);
#endif
 
        /*
         * Unmark the redzone to avoid reports from consumers who are
         * (presumably) about to use the full allocation size.
         */
        kasan_mark(addr, size, size, 0);
 
        return (size);
}
 
CTASSERT(VM_KMEM_SIZE_SCALE >= 1);
 
/*
 * Initialize the kernel memory (kmem) arena.
 */
void
kmeminit(void)
{
        u_long mem_size;
        u_long tmp;
 
#ifdef VM_KMEM_SIZE
        if (vm_kmem_size == 0)
                vm_kmem_size = VM_KMEM_SIZE;
#endif
#ifdef VM_KMEM_SIZE_MIN
        if (vm_kmem_size_min == 0)
                vm_kmem_size_min = VM_KMEM_SIZE_MIN;
#endif
#ifdef VM_KMEM_SIZE_MAX
        if (vm_kmem_size_max == 0)
                vm_kmem_size_max = VM_KMEM_SIZE_MAX;
#endif
        /*
         * Calculate the amount of kernel virtual address (KVA) space that is
         * preallocated to the kmem arena.  In order to support a wide range
         * of machines, it is a function of the physical memory size,
         * specifically,
         *
         *      min(max(physical memory size / VM_KMEM_SIZE_SCALE,
         *          VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX)
         *
         * Every architecture must define an integral value for
         * VM_KMEM_SIZE_SCALE.  However, the definitions of VM_KMEM_SIZE_MIN
         * and VM_KMEM_SIZE_MAX, which represent respectively the floor and
         * ceiling on this preallocation, are optional.  Typically,
         * VM_KMEM_SIZE_MAX is itself a function of the available KVA space on
         * a given architecture.
         */
        mem_size = vm_cnt.v_page_count;
        if (mem_size <= 32768) /* delphij XXX 128MB */
                kmem_zmax = PAGE_SIZE;
 
        if (vm_kmem_size_scale < 1)
                vm_kmem_size_scale = VM_KMEM_SIZE_SCALE;
 
        /*
         * Check if we should use defaults for the "vm_kmem_size"
         * variable:
         */
        if (vm_kmem_size == 0) {
                vm_kmem_size = mem_size / vm_kmem_size_scale;
                vm_kmem_size = vm_kmem_size * PAGE_SIZE < vm_kmem_size ?
                    vm_kmem_size_max : vm_kmem_size * PAGE_SIZE;
                if (vm_kmem_size_min > 0 && vm_kmem_size < vm_kmem_size_min)
                        vm_kmem_size = vm_kmem_size_min;
                if (vm_kmem_size_max > 0 && vm_kmem_size >= vm_kmem_size_max)
                        vm_kmem_size = vm_kmem_size_max;
        }
        if (vm_kmem_size == 0)
                panic("Tune VM_KMEM_SIZE_* for the platform");
 
        /*
         * The amount of KVA space that is preallocated to the
         * kmem arena can be set statically at compile-time or manually
         * through the kernel environment.  However, it is still limited to
         * twice the physical memory size, which has been sufficient to handle
         * the most severe cases of external fragmentation in the kmem arena. 
         */
        if (vm_kmem_size / 2 / PAGE_SIZE > mem_size)
                vm_kmem_size = 2 * mem_size * PAGE_SIZE;
 
        vm_kmem_size = round_page(vm_kmem_size);
 
        /*
         * With KASAN or KMSAN enabled, dynamically allocated kernel memory is
         * shadowed.  Account for this when setting the UMA limit.
         */
#if defined(KASAN)
        vm_kmem_size = (vm_kmem_size * KASAN_SHADOW_SCALE) /
            (KASAN_SHADOW_SCALE + 1);
#elif defined(KMSAN)
        vm_kmem_size /= 3;
#endif
 
#ifdef DEBUG_MEMGUARD
        tmp = memguard_fudge(vm_kmem_size, kernel_map);
#else
        tmp = vm_kmem_size;
#endif
        uma_set_limit(tmp);
 
#ifdef DEBUG_MEMGUARD
        /*
         * Initialize MemGuard if support compiled in.  MemGuard is a
         * replacement allocator used for detecting tamper-after-free
         * scenarios as they occur.  It is only used for debugging.
         */
        memguard_init(kernel_arena);
#endif
}
 
/*
 * Initialize the kernel memory allocator
 */
/* ARGSUSED*/
static void
mallocinit(void *dummy)
{
        int i;
        uint8_t indx;
 
        mtx_init(&malloc_mtx, "malloc", NULL, MTX_DEF);
 
        kmeminit();
 
        if (kmem_zmax < PAGE_SIZE || kmem_zmax > KMEM_ZMAX)
                kmem_zmax = KMEM_ZMAX;
 
        for (i = 0, indx = 0; kmemzones[indx].kz_size != 0; indx++) {
                int size = kmemzones[indx].kz_size;
                const char *name = kmemzones[indx].kz_name;
                size_t align;
                int subzone;
 
                align = UMA_ALIGN_PTR;
                if (powerof2(size) && size > sizeof(void *))
                        align = MIN(size, PAGE_SIZE) - 1;
                for (subzone = 0; subzone < numzones; subzone++) {
                        kmemzones[indx].kz_zone[subzone] =
                            uma_zcreate(name, size,
#if defined(INVARIANTS) && !defined(KASAN) && !defined(KMSAN)
                            mtrash_ctor, mtrash_dtor, mtrash_init, mtrash_fini,
#else
                            NULL, NULL, NULL, NULL,
#endif
                            align, UMA_ZONE_MALLOC);
                }
                for (;i <= size; i+= KMEM_ZBASE)
                        kmemsize[i >> KMEM_ZSHIFT] = indx;
        }
}
SYSINIT(kmem, SI_SUB_KMEM, SI_ORDER_SECOND, mallocinit, NULL);
 
void
malloc_init(void *data)
{
        struct malloc_type_internal *mtip;
        struct malloc_type *mtp;
 
        KASSERT(vm_cnt.v_page_count != 0, ("malloc_register before vm_init"));
 
        mtp = data;
        if (mtp->ks_version != M_VERSION)
                panic("malloc_init: type %s with unsupported version %lu",
                    mtp->ks_shortdesc, mtp->ks_version);
 
        mtip = &mtp->ks_mti;
        mtip->mti_stats = uma_zalloc_pcpu(pcpu_zone_64, M_WAITOK | M_ZERO);
        mtp_set_subzone(mtp);
 
        mtx_lock(&malloc_mtx);
        mtp->ks_next = kmemstatistics;
        kmemstatistics = mtp;
        kmemcount++;
        mtx_unlock(&malloc_mtx);
}
 
void
malloc_uninit(void *data)
{
        struct malloc_type_internal *mtip;
        struct malloc_type_stats *mtsp;
        struct malloc_type *mtp, *temp;
        long temp_allocs, temp_bytes;
        int i;
 
        mtp = data;
        KASSERT(mtp->ks_version == M_VERSION,
            ("malloc_uninit: bad malloc type version"));
 
        mtx_lock(&malloc_mtx);
        mtip = &mtp->ks_mti;
        if (mtp != kmemstatistics) {
                for (temp = kmemstatistics; temp != NULL;
                    temp = temp->ks_next) {
                        if (temp->ks_next == mtp) {
                                temp->ks_next = mtp->ks_next;
                                break;
                        }
                }
                KASSERT(temp,
                    ("malloc_uninit: type '%s' not found", mtp->ks_shortdesc));
        } else
                kmemstatistics = mtp->ks_next;
        kmemcount--;
        mtx_unlock(&malloc_mtx);
 
        /*
         * Look for memory leaks.
         */
        temp_allocs = temp_bytes = 0;
        for (i = 0; i <= mp_maxid; i++) {
                mtsp = zpcpu_get_cpu(mtip->mti_stats, i);
                temp_allocs += mtsp->mts_numallocs;
                temp_allocs -= mtsp->mts_numfrees;
                temp_bytes += mtsp->mts_memalloced;
                temp_bytes -= mtsp->mts_memfreed;
        }
        if (temp_allocs > 0 || temp_bytes > 0) {
                printf("Warning: memory type %s leaked memory on destroy "
                    "(%ld allocations, %ld bytes leaked).\n", mtp->ks_shortdesc,
                    temp_allocs, temp_bytes);
        }
 
        uma_zfree_pcpu(pcpu_zone_64, mtip->mti_stats);
}
 
struct malloc_type *
malloc_desc2type(const char *desc)
{
        struct malloc_type *mtp;
 
        mtx_assert(&malloc_mtx, MA_OWNED);
        for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
                if (strcmp(mtp->ks_shortdesc, desc) == 0)
                        return (mtp);
        }
        return (NULL);
}
 
static int
sysctl_kern_malloc_stats(SYSCTL_HANDLER_ARGS)
{
        struct malloc_type_stream_header mtsh;
        struct malloc_type_internal *mtip;
        struct malloc_type_stats *mtsp, zeromts;
        struct malloc_type_header mth;
        struct malloc_type *mtp;
        int error, i;
        struct sbuf sbuf;
 
        error = sysctl_wire_old_buffer(req, 0);
        if (error != 0)
                return (error);
        sbuf_new_for_sysctl(&sbuf, NULL, 128, req);
        sbuf_clear_flags(&sbuf, SBUF_INCLUDENUL);
        mtx_lock(&malloc_mtx);
 
        bzero(&zeromts, sizeof(zeromts));
 
        /*
         * Insert stream header.
         */
        bzero(&mtsh, sizeof(mtsh));
        mtsh.mtsh_version = MALLOC_TYPE_STREAM_VERSION;
        mtsh.mtsh_maxcpus = MAXCPU;
        mtsh.mtsh_count = kmemcount;
        (void)sbuf_bcat(&sbuf, &mtsh, sizeof(mtsh));
 
        /*
         * Insert alternating sequence of type headers and type statistics.
         */
        for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
                mtip = &mtp->ks_mti;
 
                /*
                 * Insert type header.
                 */
                bzero(&mth, sizeof(mth));
                strlcpy(mth.mth_name, mtp->ks_shortdesc, MALLOC_MAX_NAME);
                (void)sbuf_bcat(&sbuf, &mth, sizeof(mth));
 
                /*
                 * Insert type statistics for each CPU.
                 */
                for (i = 0; i <= mp_maxid; i++) {
                        mtsp = zpcpu_get_cpu(mtip->mti_stats, i);
                        (void)sbuf_bcat(&sbuf, mtsp, sizeof(*mtsp));
                }
                /*
                 * Fill in the missing CPUs.
                 */
                for (; i < MAXCPU; i++) {
                        (void)sbuf_bcat(&sbuf, &zeromts, sizeof(zeromts));
                }
        }
        mtx_unlock(&malloc_mtx);
        error = sbuf_finish(&sbuf);
        sbuf_delete(&sbuf);
        return (error);
}
 
SYSCTL_PROC(_kern, OID_AUTO, malloc_stats,
    CTLFLAG_RD | CTLTYPE_STRUCT | CTLFLAG_MPSAFE, 0, 0,
    sysctl_kern_malloc_stats, "s,malloc_type_ustats",
    "Return malloc types");
 
SYSCTL_INT(_kern, OID_AUTO, malloc_count, CTLFLAG_RD, &kmemcount, 0,
    "Count of kernel malloc types");
 
void
malloc_type_list(malloc_type_list_func_t *func, void *arg)
{
        struct malloc_type *mtp, **bufmtp;
        int count, i;
        size_t buflen;
 
        mtx_lock(&malloc_mtx);
restart:
        mtx_assert(&malloc_mtx, MA_OWNED);
        count = kmemcount;
        mtx_unlock(&malloc_mtx);
 
        buflen = sizeof(struct malloc_type *) * count;
        bufmtp = malloc(buflen, M_TEMP, M_WAITOK);
 
        mtx_lock(&malloc_mtx);
 
        if (count < kmemcount) {
                free(bufmtp, M_TEMP);
                goto restart;
        }
 
        for (mtp = kmemstatistics, i = 0; mtp != NULL; mtp = mtp->ks_next, i++)
                bufmtp[i] = mtp;
 
        mtx_unlock(&malloc_mtx);
 
        for (i = 0; i < count; i++)
                (func)(bufmtp[i], arg);
 
        free(bufmtp, M_TEMP);
}
 
#ifdef DDB
static int64_t
get_malloc_stats(const struct malloc_type_internal *mtip, uint64_t *allocs,
    uint64_t *inuse)
{
        const struct malloc_type_stats *mtsp;
        uint64_t frees, alloced, freed;
        int i;
 
        *allocs = 0;
        frees = 0;
        alloced = 0;
        freed = 0;
        for (i = 0; i <= mp_maxid; i++) {
                mtsp = zpcpu_get_cpu(mtip->mti_stats, i);
 
                *allocs += mtsp->mts_numallocs;
                frees += mtsp->mts_numfrees;
                alloced += mtsp->mts_memalloced;
                freed += mtsp->mts_memfreed;
        }
        *inuse = *allocs - frees;
        return (alloced - freed);
}
 
DB_SHOW_COMMAND(malloc, db_show_malloc)
{
        const char *fmt_hdr, *fmt_entry;
        struct malloc_type *mtp;
        uint64_t allocs, inuse;
        int64_t size;
        /* variables for sorting */
        struct malloc_type *last_mtype, *cur_mtype;
        int64_t cur_size, last_size;
        int ties;
 
        if (modif[0] == 'i') {
                fmt_hdr = "%s,%s,%s,%s\n";
                fmt_entry = "\"%s\",%ju,%jdK,%ju\n";
        } else {
                fmt_hdr = "%18s %12s  %12s %12s\n";
                fmt_entry = "%18s %12ju %12jdK %12ju\n";
        }
 
        db_printf(fmt_hdr, "Type", "InUse", "MemUse", "Requests");
 
        /* Select sort, largest size first. */
        last_mtype = NULL;
        last_size = INT64_MAX;
        for (;;) {
                cur_mtype = NULL;
                cur_size = -1;
                ties = 0;
 
                for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
                        /*
                         * In the case of size ties, print out mtypes
                         * in the order they are encountered.  That is,
                         * when we encounter the most recently output
                         * mtype, we have already printed all preceding
                         * ties, and we must print all following ties.
                         */
                        if (mtp == last_mtype) {
                                ties = 1;
                                continue;
                        }
                        size = get_malloc_stats(&mtp->ks_mti, &allocs,
                            &inuse);
                        if (size > cur_size && size < last_size + ties) {
                                cur_size = size;
                                cur_mtype = mtp;
                        }
                }
                if (cur_mtype == NULL)
                        break;
 
                size = get_malloc_stats(&cur_mtype->ks_mti, &allocs, &inuse);
                db_printf(fmt_entry, cur_mtype->ks_shortdesc, inuse,
                    howmany(size, 1024), allocs);
 
                if (db_pager_quit)
                        break;
 
                last_mtype = cur_mtype;
                last_size = cur_size;
        }
}
 
#if MALLOC_DEBUG_MAXZONES > 1
DB_SHOW_COMMAND(multizone_matches, db_show_multizone_matches)
{
        struct malloc_type_internal *mtip;
        struct malloc_type *mtp;
        u_int subzone;
 
        if (!have_addr) {
                db_printf("Usage: show multizone_matches <malloc type/addr>\n");
                return;
        }
        mtp = (void *)addr;
        if (mtp->ks_version != M_VERSION) {
                db_printf("Version %lx does not match expected %x\n",
                    mtp->ks_version, M_VERSION);
                return;
        }
 
        mtip = &mtp->ks_mti;
        subzone = mtip->mti_zone;
 
        for (mtp = kmemstatistics; mtp != NULL; mtp = mtp->ks_next) {
                mtip = &mtp->ks_mti;
                if (mtip->mti_zone != subzone)
                        continue;
                db_printf("%s\n", mtp->ks_shortdesc);
                if (db_pager_quit)
                        break;
        }
}
#endif /* MALLOC_DEBUG_MAXZONES > 1 */
#endif /* DDB */