Logo Search packages:      
Sourcecode: makefs version File versions  Download package

ffs_subr.c

/*    $OpenBSD: ffs_subr.c,v 1.15 2004/01/20 03:44:06 tedu Exp $  */
/*    $NetBSD: ffs_subr.c,v 1.6 1996/03/17 02:16:23 christos Exp $      */

/*
 * 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
 */

#include <sys/param.h>
#include <ufs/ffs/fs.h>

#ifdef _KERNEL
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/buf.h>

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

#include <ufs/ffs/ffs_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
ffs_bufatoff(struct inode *ip, off_t offset, char **res, struct buf **bpp)
{
      struct fs *fs;
      struct vnode *vp;
      struct buf *bp;
      daddr_t lbn;
      int bsize, error;

      vp = ITOV(ip);
      fs = ip->i_fs;
      lbn = lblkno(fs, offset);
      bsize = blksize(fs, ip, lbn);

      *bpp = NULL;
      if ((error = bread(vp, lbn, bsize, NOCRED, &bp)) != 0) {
            brelse(bp);
            return (error);
      }
      if (res)
            *res = (char *)bp->b_data + blkoff(fs, offset);
      *bpp = bp;
      return (0);
}
#else
/* Prototypes for userland */
void  ffs_fragacct(struct fs *, int, int32_t[], int);
int   ffs_isfreeblock(struct fs *, unsigned char *, daddr_t);
int   ffs_isblock(struct fs *, unsigned char *, daddr_t);
void  ffs_clrblock(struct fs *, u_char *, daddr_t);
void  ffs_setblock(struct fs *, unsigned char *, daddr_t);
__dead void panic(const char *, ...);
#endif

/*
 * Update the frsum fields to reflect addition or deletion
 * of some frags.
 */
void
ffs_fragacct(fs, fragmap, fraglist, cnt)
      struct fs *fs;
      int fragmap;
      int32_t fraglist[];
      int cnt;
{
      int inblk;
      register int field, subfield;
      register int siz, pos;

      inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1;
      fragmap <<= 1;
      for (siz = 1; siz < fs->fs_frag; siz++) {
            if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0)
                  continue;
            field = around[siz];
            subfield = inside[siz];
            for (pos = siz; pos <= fs->fs_frag; pos++) {
                  if ((fragmap & field) == subfield) {
                        fraglist[siz] += cnt;
                        pos += siz;
                        field <<= siz;
                        subfield <<= siz;
                  }
                  field <<= 1;
                  subfield <<= 1;
            }
      }
}

#if defined(_KERNEL) && defined(DIAGNOSTIC)
void
ffs_checkoverlap(bp, ip)
      struct buf *bp;
      struct inode *ip;
{
      register struct buf *ebp, *ep;
      register daddr_t start, last;
      struct vnode *vp;

      ebp = &buf[nbuf];
      start = bp->b_blkno;
      last = start + btodb(bp->b_bcount) - 1;
      for (ep = buf; ep < ebp; ep++) {
            if (ep == bp || (ep->b_flags & B_INVAL) ||
                ep->b_vp == NULLVP)
                  continue;
            if (VOP_BMAP(ep->b_vp, (daddr_t)0, &vp, (daddr_t)0, NULL))
                  continue;
            if (vp != ip->i_devvp)
                  continue;
            /* look for overlap */
            if (ep->b_bcount == 0 || ep->b_blkno > last ||
                ep->b_blkno + btodb(ep->b_bcount) <= start)
                  continue;
            vprint("Disk overlap", vp);
            (void)printf("\tstart %d, end %d overlap start %d, end %ld\n",
                  start, last, ep->b_blkno,
                  ep->b_blkno + btodb(ep->b_bcount) - 1);
            panic("Disk buffer overlap");
      }
}
#endif /* DIAGNOSTIC */

/*
 * block operations
 *
 * check if a block is available
 */
int
ffs_isblock(fs, cp, h)
      struct fs *fs;
      unsigned char *cp;
      daddr_t h;
{
      unsigned char mask;

      switch ((int)fs->fs_frag) {
      case 8:
            return (cp[h] == 0xff);
      case 4:
            mask = 0x0f << ((h & 0x1) << 2);
            return ((cp[h >> 1] & mask) == mask);
      case 2:
            mask = 0x03 << ((h & 0x3) << 1);
            return ((cp[h >> 2] & mask) == mask);
      case 1:
            mask = 0x01 << (h & 0x7);
            return ((cp[h >> 3] & mask) == mask);
      default:
            panic("ffs_isblock");
      }
}

/*
 * take a block out of the map
 */
void
ffs_clrblock(fs, cp, h)
      struct fs *fs;
      u_char *cp;
      daddr_t h;
{

      switch ((int)fs->fs_frag) {
      case 8:
            cp[h] = 0;
            return;
      case 4:
            cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
            return;
      case 2:
            cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
            return;
      case 1:
            cp[h >> 3] &= ~(0x01 << (h & 0x7));
            return;
      default:
            panic("ffs_clrblock");
      }
}

/*
 * put a block into the map
 */
void
ffs_setblock(fs, cp, h)
      struct fs *fs;
      unsigned char *cp;
      daddr_t h;
{

      switch ((int)fs->fs_frag) {

      case 8:
            cp[h] = 0xff;
            return;
      case 4:
            cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
            return;
      case 2:
            cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
            return;
      case 1:
            cp[h >> 3] |= (0x01 << (h & 0x7));
            return;
      default:
            panic("ffs_setblock");
      }
}


/*
 * check if a block is free
 */
int
ffs_isfreeblock(fs, cp, h)
      struct fs *fs;
      unsigned char *cp;
      daddr_t h;
{

      switch ((int)fs->fs_frag) {
      case 8:
            return (cp[h] == 0);
      case 4:
            return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0);
      case 2:
            return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0);
      case 1:
            return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0);
      default:
            panic("ffs_isfreeblock");
      }
}

Generated by  Doxygen 1.6.0   Back to index