rcap/rcapd/rcapd_mapping.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <assert.h>
#include <stdlib.h>
#include "rcapd_mapping.h"
#include "utils.h"

/*
 * lmapping_t is a list of non-overlapping mappings, ordered by address.  These
 * functions add, remove, and verify the existence of mappings in such a list.
 * rcapd_scanner.c is a consumer.
 */

typedef struct lmapping_find_cb_arg {
    uintptr_t   lmfa_addr;
    size_t      lmfa_size;
    lmapping_t  *lmfa_prior;
    lmapping_t  *lmfa_ret;
} lmapping_find_cb_arg_t;

#ifdef DEBUG
/*
 * Verify a sublist is properly ordered.
 */
static void
lmapping_verify(lmapping_t *lm)
{
    while (lm != NULL) {
        if (lm->lm_next != NULL)
            ASSERT(lm->lm_next->lm_addr > lm->lm_addr);
        lm = lm->lm_next;
    }
}
#else /* !DEBUG */
#define lmapping_verify(x) ((void)0)
#endif /* DEBUG */

/*
 * Determine the position of a mapping with the given address and size.  Upon
 * return, lmfa_ret will be set to the actual mapping, if it exists, and
 * lmfa_prior will be set to the mapping which does or would precede one with
 * the given characteristics.
 */
static int
lmapping_find_cb(lmapping_t *lm, void *arg)
{
    lmapping_find_cb_arg_t *lmfa = arg;

    if (lm->lm_addr >= lmfa->lmfa_addr) {
        if (lmfa->lmfa_addr == lm->lm_addr && lmfa->lmfa_size ==
            lm->lm_size)
            lmfa->lmfa_ret = lm;
        return (1);
    } else
        lmfa->lmfa_prior = lm;

    return (0);
}

static void
lmapping_walk(lmapping_t *lm, int(*lmapping_walk_cb)(lmapping_t *, void *),
    void *arg)
{
    lmapping_t *next;

    while (lm != NULL) {
        next = lm->lm_next;
        lmapping_verify(lm);
        if (lmapping_walk_cb(lm, arg) != 0) {
            lmapping_verify(lm);
            return;
        }
        lm = next;
    }
}

int
lmapping_remove(lmapping_t **lm, uintptr_t addr, size_t size)
{
    lmapping_find_cb_arg_t lmfa;

    lmfa.lmfa_addr = addr;
    lmfa.lmfa_size = size;
    lmfa.lmfa_prior = lmfa.lmfa_ret = NULL;

    lmapping_verify(*lm);
    lmapping_walk(*lm, lmapping_find_cb, &lmfa);
    if (lmfa.lmfa_ret == NULL)
        return (-1);

    if (lmfa.lmfa_prior != NULL)
        lmfa.lmfa_prior->lm_next = lmfa.lmfa_ret->lm_next;
    else if (*lm == lmfa.lmfa_ret)
        *lm = lmfa.lmfa_ret->lm_next;

    free(lmfa.lmfa_ret);

    lmapping_verify(*lm);

    return (0);
}

int
lmapping_insert(lmapping_t **lm, uintptr_t addr, size_t size)
{
    lmapping_find_cb_arg_t lmfa;
    lmapping_t *cur;

    cur = malloc(sizeof (*cur));
    if (cur == NULL)
        return (-1);

    cur->lm_addr = addr;
    cur->lm_size = size;
    cur->lm_next = NULL;

    lmfa.lmfa_addr = addr;
    lmfa.lmfa_size = size;
    lmfa.lmfa_prior = lmfa.lmfa_ret = NULL;

    lmapping_verify(*lm);
    lmapping_walk(*lm, lmapping_find_cb, &lmfa);
    ASSERT(lmfa.lmfa_ret == NULL);
    if (lmfa.lmfa_prior != NULL) {
        cur->lm_next = lmfa.lmfa_prior->lm_next;
        lmfa.lmfa_prior->lm_next = cur;
    } else {
        cur->lm_next = *lm;
        *lm = cur;
    }

    lmapping_verify(*lm);

    return (0);
}

int
lmapping_contains(lmapping_t *lm, uintptr_t addr, size_t size)
{
    lmapping_find_cb_arg_t lmfa;

    lmfa.lmfa_addr = addr;
    lmfa.lmfa_size = size;
    lmfa.lmfa_ret = NULL;

    lmapping_walk(lm, lmapping_find_cb, &lmfa);
    return (lmfa.lmfa_ret != NULL);
}

/*ARGSUSED*/
static int
lmapping_free_cb(lmapping_t *lm, void *arg)
{
    free(lm);
    return (0);
}

void
lmapping_free(lmapping_t **lm)
{
    lmapping_walk(*lm, lmapping_free_cb, NULL);
    *lm = NULL;
}

#ifdef DEBUG
int
lmapping_dump_diff(lmapping_t *lm1, lmapping_t *lm2)
{
    lmapping_t **lmv;
    int res = 0;
    int ch = 0;
    int label_printed = 0;

#define OUTPUT_LABEL() \
    if (label_printed == 0) { \
        debug("changes in mappings:\n"); \
        label_printed++; \
    }

    while (lm1 != NULL && lm2 != NULL) {
        if ((lm1->lm_addr != lm2->lm_addr) || (lm1->lm_size !=
            lm2->lm_size)) {
            res = -1;

            if (lm1->lm_addr == lm2->lm_addr && lm1->lm_size <
                lm2->lm_size || lm1->lm_addr < lm2->lm_addr) {
                lmv = &lm1;
                ch = '-';
            } else {
                lmv = &lm2;
                ch = '+';
            }
            OUTPUT_LABEL();
            debug("%c%p+0x%llx\n", ch, (void *)(*lmv)->lm_addr,
                (long long)(*lmv)->lm_size);
            *lmv = (*lmv)->lm_next;
        } else {
            lm1 = lm1->lm_next;
            lm2 = lm2->lm_next;
        }
    }
    while (lm1 != NULL) {
        OUTPUT_LABEL();
        debug("%c%p+0x%llx\n", '-', (void *)lm1->lm_addr,
            (unsigned long long)lm1->lm_size);
        lm1 = lm1->lm_next;
        res = 1;
    }
    while (lm2 != NULL) {
        OUTPUT_LABEL();
        debug("%c%p+0x%llx\n", '+', (void *)lm2->lm_addr,
            (long long)lm2->lm_size);
        lm2 = lm2->lm_next;
        res = 1;
    }

    return (res);
#undef OUTPUT_LABEL
}
#endif /* DEBUG */