/*      $OpenBSD: ext2fs_subr.c,v 1.38 2024/10/08 02:58:26 jsg Exp $    */
/*      $NetBSD: ext2fs_subr.c,v 1.1 1997/06/11 09:34:03 bouyer Exp $   */

/*
 * Copyright (c) 1997 Manuel Bouyer.
 * 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
 * Modified for ext2fs by Manuel Bouyer.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/specdev.h>

#include <ufs/ufs/quota.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/ufsmount.h>

#include <ufs/ext2fs/ext2fs.h>
#include <ufs/ext2fs/ext2fs_extern.h>
#include <ufs/ext2fs/ext2fs_extents.h>

#ifdef _KERNEL

/*
 * 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
ext2fs_bufatoff(struct inode *ip, off_t offset, char **res, struct buf **bpp)
{
        struct vnode *vp;
        struct m_ext2fs *fs;
        struct buf *bp;
        daddr_t lbn, pos;
        int error;

        vp = ITOV(ip);
        fs = ip->i_e2fs;
        lbn = lblkno(fs, offset);

        if (ip->i_e2din->e2di_flags & EXT4_EXTENTS) {
                struct ext4_extent_path path;
                struct ext4_extent *ep;

                memset(&path, 0, sizeof path);
                if (ext4_ext_find_extent(fs, ip, lbn, &path) == NULL ||
                    (ep = path.ep_ext) == NULL)
                        goto normal;

                if (path.ep_bp != NULL) {
                        brelse(path.ep_bp);
                        path.ep_bp = NULL;
                }
                pos = lbn - ep->e_blk + (((daddr_t)ep->e_start_hi << 32) | ep->e_start_lo);
                error = bread(ip->i_devvp, fsbtodb(fs, pos), fs->e2fs_bsize, &bp);
                if (error) {
                        brelse(bp);
                        return (error);
                }

                if (res)
                        *res = (char *)bp->b_data + blkoff(fs, offset);

                *bpp = bp;

                return (0);
        }

 normal:
        *bpp = NULL;
        if ((error = bread(vp, lbn, fs->e2fs_bsize, &bp)) != 0) {
                brelse(bp);
                return (error);
        }
        if (res)
                *res = (char *)bp->b_data + blkoff(fs, offset);
        *bpp = bp;
        return (0);
}
#endif

/*
 * Initialize the vnode associated with a new inode, handle aliased vnodes.
 */
int
ext2fs_vinit(struct mount *mp, struct vnode **vpp)
{
        struct inode *ip;
        struct vnode *vp, *nvp;
        struct timeval tv;

        vp = *vpp;
        ip = VTOI(vp);
        vp->v_type = IFTOVT(ip->i_e2fs_mode);

        switch(vp->v_type) {
        case VCHR:
        case VBLK:
                vp->v_op = &ext2fs_specvops;

                nvp = checkalias(vp, letoh32(ip->i_e2din->e2di_rdev), mp);
                if (nvp != NULL) {
                        /*
                         * Discard unneeded vnode, but save its inode. Note
                         * that the lock is carried over in the inode to the
                         * replacement vnode.
                         */
                        nvp->v_data = vp->v_data;
                        vp->v_data = NULL;
                        vp->v_op = &spec_vops;
#ifdef VFSLCKDEBUG
                        vp->v_flag &= ~VLOCKSWORK;
#endif
                        vrele(vp);
                        vgone(vp);
                        /* Reinitialize aliased vnode. */
                        vp = nvp;
                        ip->i_vnode = vp;
                }

                break;

        case VFIFO:
#ifdef FIFO
                vp->v_op = &ext2fs_fifovops;
                break;
#else
                return (EOPNOTSUPP);
#endif /* FIFO */

        default:

                break;
        }

        if (ip->i_number == EXT2_ROOTINO)
                vp->v_flag |= VROOT;

        /* Initialize modrev times */
        getmicrouptime(&tv);
        ip->i_modrev = (u_quad_t)tv.tv_sec << 32;
        ip->i_modrev |= (u_quad_t)tv.tv_usec * 4294;

        *vpp = vp;

        return (0);
}