usr/src/sys/ufs/lfs/lfs_subr.c

/*
 * Copyright (c) 1986, 1989, 1991 Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)lfs_subr.c  7.1 (Berkeley) %G%
 */

#include <sys/param.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/buf.h>

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

#include <ufs/lfs/lfs.h>
#include <ufs/lfs/lfs_extern.h>

/*
 * 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
lfs_blkatoff(ip, offset, res, bpp)
        struct inode *ip;
        off_t offset;
        char **res;
        struct buf **bpp;
{
        register struct lfs *fs;
        struct buf *bp;
        daddr_t lbn;
        int bsize, error;

        fs = ip->i_lfs;
        lbn = lblkno(fs, offset);
        bsize = blksize(fs);

        *bpp = NULL;
        if (error = bread(ITOV(ip), lbn, bsize, NOCRED, &bp)) {
                brelse(bp);
                return (error);
        }
        if (res)
                *res = bp->b_un.b_addr + blkoff(fs, offset);
        *bpp = bp;
        return (0);
}

/* Return the current version number for a specific inode. */
u_long
lfs_getversion(fs, ino)
        struct lfs *fs;
        ino_t ino;
{
        BUF *bp;
        IFILE *ifp;
        u_long version;

        /*
         * Read the appropriate block from the ifile.  Return the
         * version number.
         */
        LFS_IENTRY(ifp, fs, ino, bp);
        version = ifp->if_version;
        brelse(bp);
        return (version);
}

/* Search a block for a specific dinode. */
DINODE *
lfs_ifind(fs, ino, page)
        struct lfs *fs;
        ino_t ino;
        void *page;
{
        register DINODE *dip;
        register int cnt;

#ifdef ALLOCPRINT
        printf("lfs_ifind: inode %d\n", ino);
#endif
        dip = page;
        for (cnt = INOPB(fs); cnt--; ++dip)
                if (dip->di_inum == ino)
                        return (dip);

        panic("lfs_ifind: dinode %u not found", ino);
        /* NOTREACHED */
}

/* Set values in the ifile for the inode. */
void
lfs_iset(ip, daddr, atime)
        INODE *ip;
        daddr_t daddr;
        time_t atime;
{
        BUF *bp;
        IFILE *ifp;
        struct lfs *fs;
        ino_t ino;

#ifdef ALLOCPRINT
        printf("lfs_iset: setting ino %d daddr %lx time %lx\n",
            ip->i_number, daddr, atime);
#endif

        fs = ip->i_lfs;
        ino = ip->i_number;
        LFS_IENTRY(ifp, fs, ino, bp);

        ifp->if_daddr = daddr;
        ifp->if_st_atime = atime;
        lfs_bwrite(bp);
}

/* Translate an inode number to a disk address. */
daddr_t
lfs_itod(fs, ino)
        struct lfs *fs;
        ino_t ino;
{
        BUF *bp;
        IFILE *ifp;
        daddr_t iaddr;

        /* Read the appropriate block from the ifile. */
        LFS_IENTRY(ifp, fs, ino, bp);

        if (ifp->if_daddr == LFS_UNUSED_DADDR)
                panic("itod: unused disk address");
        iaddr = ifp->if_daddr;
        brelse(bp);
        return (iaddr);
}