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

buf.c

/*    $NetBSD: buf.c,v 1.12 2004/06/20 22:20:18 jmc Exp $   */

/*
 * Copyright (c) 2009 Thorsten Glaser <tg@mirbsd.org>
 * Copyright (c) 2001 Wasabi Systems, Inc.
 * All rights reserved.
 *
 * Written by Luke Mewburn for Wasabi Systems, Inc.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed for the NetBSD Project by
 *      Wasabi Systems, Inc.
 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
 * 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.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/cdefs.h>
#if defined(__RCSID) && !defined(__lint)
__RCSID("$NetBSD: buf.c,v 1.12 2004/06/20 22:20:18 jmc Exp $");
__IDSTRING(mbsdid, "$MirOS: src/usr.sbin/makefs/ffs/buf.c,v 1.2 2009/07/23 19:32:25 tg Exp $");
#endif      /* !__lint */

#include <sys/param.h>
#include <sys/time.h>

#include <assert.h>
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "makefs.h"

#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#include "ffs/buf.h"
#include "ffs/ufs_inode.h"

extern int sectorsize;        /* XXX: from ffs.c & mkfs.c */

TAILQ_HEAD(buftailhead,buf) buftail;

int
bread(int fd, struct fs *fs, daddr_t blkno, int size, struct buf **bpp)
{
      off_t offset;
      ssize_t     rv;

      assert (fs != NULL);
      assert (bpp != NULL);

      if (debug & DEBUG_BUF_BREAD)
            printf("bread: fs %p blkno %lld size %d\n",
                fs, (long long)blkno, size);
      *bpp = getblk(fd, fs, blkno, size);
      offset = (*bpp)->b_blkno * sectorsize;    /* XXX */
      if (debug & DEBUG_BUF_BREAD)
            printf("bread: bp %p blkno %lld offset %lld bcount %ld\n",
                (*bpp), (long long)(*bpp)->b_blkno, (long long) offset,
                (*bpp)->b_bcount);
      if (lseek((*bpp)->b_fd, offset, SEEK_SET) == -1)
            err(1, "bread: lseek %lld (%lld)",
                (long long)(*bpp)->b_blkno, (long long)offset);
      rv = read((*bpp)->b_fd, (*bpp)->b_data, (*bpp)->b_bcount);
      if (debug & DEBUG_BUF_BREAD)
            printf("bread: read %ld (%lld) returned %d\n",
                (*bpp)->b_bcount, (long long)offset, (int)rv);
      if (rv == -1)                       /* read error */
            err(1, "bread: read %ld (%lld) returned %d",
                (*bpp)->b_bcount, (long long)offset, (int)rv);
      else if (rv != (*bpp)->b_bcount)    /* short read */
            err(1, "bread: read %ld (%lld) returned %d",
                (*bpp)->b_bcount, (long long)offset, (int)rv);
      else
            return (0);
}

void
brelse(struct buf *bp)
{

      assert (bp != NULL);
      assert (bp->b_data != NULL);

      if (bp->b_lblkno < 0) {
            /*
             * XXX      don't remove any buffers with negative logical block
             *    numbers (lblkno), so that we retain the mapping
             *    of negative lblkno -> real blkno that ffs_balloc()
             *    sets up.
             *
             *    if we instead released these buffers, and implemented
             *    ufs_strategy() (and ufs_bmaparray()) and called those
             *    from bread() and bwrite() to convert the lblkno to
             *    a real blkno, we'd add a lot more code & complexity
             *    and reading off disk, for little gain, because this
             *    simple hack works for our purpose.
             */
            bp->b_bcount = 0;
            return;
      }

      TAILQ_REMOVE(&buftail, bp, b_tailq);
      free(bp->b_data);
      free(bp);
}

int
bwrite(struct buf *bp)
{
      off_t offset;
      ssize_t     rv;

      assert (bp != NULL);
      offset = bp->b_blkno * sectorsize;  /* XXX */
      if (debug & DEBUG_BUF_BWRITE)
            printf("bwrite: bp %p blkno %lld offset %lld bcount %ld\n",
                bp, (long long)bp->b_blkno, (long long) offset,
                bp->b_bcount);
      if (lseek(bp->b_fd, offset, SEEK_SET) == -1)
            return (errno);
      rv = write(bp->b_fd, bp->b_data, bp->b_bcount);
      if (debug & DEBUG_BUF_BWRITE)
            printf("bwrite: write %ld (offset %lld) returned %lld\n",
                bp->b_bcount, (long long)offset, (long long)rv);
      if (rv == bp->b_bcount)
            return (0);
      else if (rv == -1)            /* write error */
            return (errno);
      else                    /* short write ? */
            return (EAGAIN);
}

void
bcleanup(void)
{
      struct buf *bp;

      /*
       * XXX      this really shouldn't be necessary, but i'm curious to
       *    know why there's still some buffers lying around that
       *    aren't brelse()d
       */

      if (TAILQ_EMPTY(&buftail))
            return;

      printf("bcleanup: unflushed buffers:\n");
      TAILQ_FOREACH(bp, &buftail, b_tailq) {
            printf("\tlblkno %10lld  blkno %10lld  count %6ld  bufsize %6ld\n",
                (long long)bp->b_lblkno, (long long)bp->b_blkno,
                bp->b_bcount, bp->b_bufsize);
      }
      printf("bcleanup: done\n");
}

struct buf *
getblk(int fd, struct fs *fs, daddr_t blkno, int size)
{
      static int buftailinitted;
      struct buf *bp;
      void *n;

      assert (fs != NULL);
      if (debug & DEBUG_BUF_GETBLK)
            printf("getblk: fs %p blkno %lld size %d\n", fs,
                (long long)blkno, size);

      bp = NULL;
      if (!buftailinitted) {
            if (debug & DEBUG_BUF_GETBLK)
                  printf("getblk: initialising tailq\n");
            TAILQ_INIT(&buftail);
            buftailinitted = 1;
      } else {
            TAILQ_FOREACH(bp, &buftail, b_tailq) {
                  if (bp->b_lblkno != blkno)
                        continue;
                  break;
            }
      }
      if (bp == NULL) {
            if ((bp = calloc(1, sizeof(struct buf))) == NULL)
                  err(1, "getblk: calloc");

            bp->b_bufsize = 0;
            bp->b_blkno = bp->b_lblkno = blkno;
            bp->b_fd = fd;
            bp->b_fs = fs;
            bp->b_data = NULL;
            TAILQ_INSERT_HEAD(&buftail, bp, b_tailq);
      }
      bp->b_bcount = size;
      if (bp->b_data == NULL || bp->b_bcount > bp->b_bufsize) {
            n = realloc(bp->b_data, size);
            if (n == NULL)
                  err(1, "getblk: realloc b_data %ld", bp->b_bcount);
            bp->b_data = n;
            bp->b_bufsize = size;
      }

      return (bp);
}

Generated by  Doxygen 1.6.0   Back to index