/*-
 *  modified for Lites 1.1
 *
 *  Aug 1995, Godmar Back (gback@cs.utah.edu)
 *  University of Utah, Department of Computer Science
 */
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1989, 1993
 *      The Regents of the University of California.  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.
 *
 *      @(#)ffs_subr.c  8.2 (Berkeley) 9/21/93
 * $FreeBSD$
 */

#include <sys/param.h>

#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/buf2.h>
#include <sys/lock.h>
#include <sys/ucred.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/malloc.h>

#include <vfs/ext2fs/fs.h>
#include <vfs/ext2fs/inode.h>
#include <vfs/ext2fs/ext2fs.h>
#include <vfs/ext2fs/ext2_extern.h>
#include <vfs/ext2fs/fs.h>
#include <vfs/ext2fs/ext2_extents.h>
#include <vfs/ext2fs/ext2_mount.h>
#include <vfs/ext2fs/ext2_dinode.h>

void
ext2_free(void *addr, struct malloc_type *type, const char *func)
{
        if (addr == NULL) {
                printf("%s: trying to free NULL pointer\n", func);
                return;
        }
        kfree(addr, type);
}

/*
 * Return buffer with the contents of block "offset" from the beginning of
 * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
 * remaining space in the directory.
 */
int
ext2_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp)
{
        struct inode *ip;
        struct m_ext2fs *fs;
        struct buf *bp;
        e2fs_lbn_t lbn;
        int error, bsize;

        ip = VTOI(vp);
        fs = ip->i_e2fs;
        lbn = lblkno(fs, offset);
        bsize = blksize(fs, ip, lbn);

        if ((error = bread(vp, lblktodoff(fs, lbn), bsize, &bp)) != 0) {
                brelse(bp);
                return (error);
        }
        error = ext2_dir_blk_csum_verify(ip, bp);
        if (error != 0) {
                brelse(bp);
                return (error);
        }
        if (res)
                *res = (char *)bp->b_data + blkoff(fs, offset);

        *bpp = bp;

        return (0);
}

/*
 * Update the cluster map because of an allocation of free like ffs.
 *
 * Cnt == 1 means free; cnt == -1 means allocating.
 */
void
ext2_clusteracct(struct m_ext2fs *fs, char *bbp, int cg, e4fs_daddr_t bno, int cnt)
{
        int32_t *sump = fs->e2fs_clustersum[cg].cs_sum;
        int32_t *lp;
        e4fs_daddr_t start, end, loc, forw, back;
        int bit, i;

        /* Initialize the cluster summary array. */
        if (fs->e2fs_clustersum[cg].cs_init == 0) {
                int run = 0;

                bit = 1;
                loc = 0;

                for (i = 0; i < fs->e2fs_fpg; i++) {
                        if ((bbp[loc] & bit) == 0)
                                run++;
                        else if (run != 0) {
                                if (run > fs->e2fs_contigsumsize)
                                        run = fs->e2fs_contigsumsize;
                                sump[run]++;
                                run = 0;
                        }
                        if ((i & (NBBY - 1)) != (NBBY - 1))
                                bit <<= 1;
                        else {
                                loc++;
                                bit = 1;
                        }
                }
                if (run != 0) {
                        if (run > fs->e2fs_contigsumsize)
                                run = fs->e2fs_contigsumsize;
                        sump[run]++;
                }
                fs->e2fs_clustersum[cg].cs_init = 1;
        }

        if (fs->e2fs_contigsumsize <= 0)
                return;

        /* Find the size of the cluster going forward. */
        start = bno + 1;
        end = start + fs->e2fs_contigsumsize;
        if (end > fs->e2fs_fpg)
                end = fs->e2fs_fpg;
        loc = start / NBBY;
        bit = 1 << (start % NBBY);
        for (i = start; i < end; i++) {
                if ((bbp[loc] & bit) != 0)
                        break;
                if ((i & (NBBY - 1)) != (NBBY - 1))
                        bit <<= 1;
                else {
                        loc++;
                        bit = 1;
                }
        }
        forw = i - start;

        /* Find the size of the cluster going backward. */
        start = bno - 1;
        end = start - fs->e2fs_contigsumsize;
        if (end < 0)
                end = -1;
        loc = start / NBBY;
        bit = 1 << (start % NBBY);
        for (i = start; i > end; i--) {
                if ((bbp[loc] & bit) != 0)
                        break;
                if ((i & (NBBY - 1)) != 0)
                        bit >>= 1;
                else {
                        loc--;
                        bit = 1 << (NBBY - 1);
                }
        }
        back = start - i;

        /*
         * Account for old cluster and the possibly new forward and
         * back clusters.
         */
        i = back + forw + 1;
        if (i > fs->e2fs_contigsumsize)
                i = fs->e2fs_contigsumsize;
        sump[i] += cnt;
        if (back > 0)
                sump[back] -= cnt;
        if (forw > 0)
                sump[forw] -= cnt;

        /* Update cluster summary information. */
        lp = &sump[fs->e2fs_contigsumsize];
        for (i = fs->e2fs_contigsumsize; i > 0; i--)
                if (*lp-- > 0)
                        break;
        fs->e2fs_maxcluster[cg] = i;
}