source: rtems-libbsd/freebsd/sys/vm/uma_dbg.c @ 3d1e767

#include <machine/rtems-bsd-kernel-space.h>

/*-
 * Copyright (c) 2002, 2003, 2004, 2005 Jeffrey Roberson <jeff@FreeBSD.org>
 * Copyright (c) 2004, 2005 Bosko Milekic <bmilekic@FreeBSD.org>
 * 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.
 */

/*
 * uma_dbg.c    Debugging features for UMA users
 *
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <rtems/bsd/sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/queue.h>
#include <rtems/bsd/sys/lock.h>
#include <sys/mutex.h>
#include <sys/malloc.h>

#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/uma.h>
#include <vm/uma_int.h>
#include <vm/uma_dbg.h>

static const u_int32_t uma_junk = 0xdeadc0de;

/*
 * Checks an item to make sure it hasn't been overwritten since it was freed,
 * prior to subsequent reallocation.
 *
 * Complies with standard ctor arg/return
 *
 */
int
trash_ctor(void *mem, int size, void *arg, int flags)
{
        int cnt;
        u_int32_t *p;

        cnt = size / sizeof(uma_junk);

        for (p = mem; cnt > 0; cnt--, p++)
                if (*p != uma_junk) {
                        printf("Memory modified after free %p(%d) val=%x @ %p\n",
                            mem, size, *p, p);
                        return (0);
                }
        return (0);
}

/*
 * Fills an item with predictable garbage
 *
 * Complies with standard dtor arg/return
 *
 */
void
trash_dtor(void *mem, int size, void *arg)
{
        int cnt;
        u_int32_t *p;

        cnt = size / sizeof(uma_junk);

        for (p = mem; cnt > 0; cnt--, p++)
                *p = uma_junk;
}

/*
 * Fills an item with predictable garbage
 *
 * Complies with standard init arg/return
 *
 */
int
trash_init(void *mem, int size, int flags)
{
        trash_dtor(mem, size, NULL);
        return (0);
}

/*
 * Checks an item to make sure it hasn't been overwritten since it was freed.
 *
 * Complies with standard fini arg/return
 *
 */
void
trash_fini(void *mem, int size)
{
        (void)trash_ctor(mem, size, NULL, 0);
}

int
mtrash_ctor(void *mem, int size, void *arg, int flags)
{
        struct malloc_type **ksp;
        u_int32_t *p = mem;
        int cnt;

        size -= sizeof(struct malloc_type *);
        ksp = (struct malloc_type **)mem;
        ksp += size / sizeof(struct malloc_type *);
        cnt = size / sizeof(uma_junk);

        for (p = mem; cnt > 0; cnt--, p++)
                if (*p != uma_junk) {
                        printf("Memory modified after free %p(%d) val=%x @ %p\n",
                            mem, size, *p, p);
                        panic("Most recently used by %s\n", (*ksp == NULL)?
                            "none" : (*ksp)->ks_shortdesc);
                }
        return (0);
}

/*
 * Fills an item with predictable garbage
 *
 * Complies with standard dtor arg/return
 *
 */
void
mtrash_dtor(void *mem, int size, void *arg)
{
        int cnt;
        u_int32_t *p;

        size -= sizeof(struct malloc_type *);
        cnt = size / sizeof(uma_junk);

        for (p = mem; cnt > 0; cnt--, p++)
                *p = uma_junk;
}

/*
 * Fills an item with predictable garbage
 *
 * Complies with standard init arg/return
 *
 */
int
mtrash_init(void *mem, int size, int flags)
{
        struct malloc_type **ksp;

        mtrash_dtor(mem, size, NULL);

        ksp = (struct malloc_type **)mem;
        ksp += (size / sizeof(struct malloc_type *)) - 1;
        *ksp = NULL;
        return (0);
}

/*
 * Checks an item to make sure it hasn't been overwritten since it was freed,
 * prior to freeing it back to available memory.
 *
 * Complies with standard fini arg/return
 *
 */
void
mtrash_fini(void *mem, int size)
{
        (void)mtrash_ctor(mem, size, NULL, 0);
}

static uma_slab_t
uma_dbg_getslab(uma_zone_t zone, void *item)
{
        uma_slab_t slab;
        uma_keg_t keg;
        u_int8_t *mem;

        mem = (u_int8_t *)((unsigned long)item & (~UMA_SLAB_MASK));
        if (zone->uz_flags & UMA_ZONE_VTOSLAB) {
                slab = vtoslab((vm_offset_t)mem);
        } else {
                keg = LIST_FIRST(&zone->uz_kegs)->kl_keg;
                if (keg->uk_flags & UMA_ZONE_HASH)
                        slab = hash_sfind(&keg->uk_hash, mem);
                else
                        slab = (uma_slab_t)(mem + keg->uk_pgoff);
        }

        return (slab);
}

/*
 * Set up the slab's freei data such that uma_dbg_free can function.
 *
 */

void
uma_dbg_alloc(uma_zone_t zone, uma_slab_t slab, void *item)
{
        uma_keg_t keg;
        uma_slabrefcnt_t slabref;
        int freei;

        if (slab == NULL) {
                slab = uma_dbg_getslab(zone, item);
                if (slab == NULL) 
                        panic("uma: item %p did not belong to zone %s\n",
                            item, zone->uz_name);
        }
        keg = slab->us_keg;

        freei = ((unsigned long)item - (unsigned long)slab->us_data)
            / keg->uk_rsize;

        if (keg->uk_flags & UMA_ZONE_REFCNT) {
                slabref = (uma_slabrefcnt_t)slab;
                slabref->us_freelist[freei].us_item = 255;
        } else {
                slab->us_freelist[freei].us_item = 255;
        }

        return;
}

/*
 * Verifies freed addresses.  Checks for alignment, valid slab membership
 * and duplicate frees.
 *
 */

void
uma_dbg_free(uma_zone_t zone, uma_slab_t slab, void *item)
{
        uma_keg_t keg;
        uma_slabrefcnt_t slabref;
        int freei;

        if (slab == NULL) {
                slab = uma_dbg_getslab(zone, item);
                if (slab == NULL) 
                        panic("uma: Freed item %p did not belong to zone %s\n",
                            item, zone->uz_name);
        }
        keg = slab->us_keg;

        freei = ((unsigned long)item - (unsigned long)slab->us_data)
            / keg->uk_rsize;

        if (freei >= keg->uk_ipers)
                panic("zone: %s(%p) slab %p freelist %d out of range 0-%d\n",
                    zone->uz_name, zone, slab, freei, keg->uk_ipers-1);

        if (((freei * keg->uk_rsize) + slab->us_data) != item) {
                printf("zone: %s(%p) slab %p freed address %p unaligned.\n",
                    zone->uz_name, zone, slab, item);
                panic("should be %p\n",
                    (freei * keg->uk_rsize) + slab->us_data);
        }

        if (keg->uk_flags & UMA_ZONE_REFCNT) {
                slabref = (uma_slabrefcnt_t)slab;
                if (slabref->us_freelist[freei].us_item != 255) {
                        printf("Slab at %p, freei %d = %d.\n",
                            slab, freei, slabref->us_freelist[freei].us_item);
                        panic("Duplicate free of item %p from zone %p(%s)\n",
                            item, zone, zone->uz_name);
                }

                /*
                 * When this is actually linked into the slab this will change.
                 * Until then the count of valid slabs will make sure we don't
                 * accidentally follow this and assume it's a valid index.
                 */
                slabref->us_freelist[freei].us_item = 0;
        } else {
                if (slab->us_freelist[freei].us_item != 255) {
                        printf("Slab at %p, freei %d = %d.\n",
                            slab, freei, slab->us_freelist[freei].us_item);
                        panic("Duplicate free of item %p from zone %p(%s)\n",
                            item, zone, zone->uz_name);
                }

                /*
                 * When this is actually linked into the slab this will change.
                 * Until then the count of valid slabs will make sure we don't
                 * accidentally follow this and assume it's a valid index.
                 */
                slab->us_freelist[freei].us_item = 0;
        }
}