示例#1
0
文件: buffer.c 项目: binsys/doc-linux
/*
 * This routine checks whether a floppy has been changed, and
 * invalidates all buffer-cache-entries in that case. This
 * is a relatively slow routine, so we have to try to minimize using
 * it. Thus it is called only upon a 'mount' or 'open'. This
 * is the best way of combining speed and utility, I think.
 * People changing diskettes in the middle of an operation deserve
 * to loose :-)
 *
 * NOTE! Although currently this is only for floppies, the idea is
 * that any additional removable block-device will use this routine,
 * and that mount/open needn't know that floppies/whatever are
 * special.
 */
void check_disk_change(int dev)
{
	int i;
	struct buffer_head * bh;

	switch(MAJOR(dev)){
	case 2: /* floppy disc */
		if (!(bh = getblk(dev,0,1024)))
			return;
		i = floppy_change(bh);
		brelse(bh);
		break;

#if defined(CONFIG_BLK_DEV_SR) && defined(CONFIG_SCSI)
         case 11: /* CDROM */
		i = check_cdrom_media_change(dev, 0);
		if (i) printk("Flushing buffers and inodes for CDROM\n");
		break;
#endif

         default:
		return;
	};

	if (!i)	return;

	for (i=0 ; i<NR_SUPER ; i++)
		if (super_block[i].s_dev == dev)
			put_super(super_block[i].s_dev);
	invalidate_inodes(dev);
	invalidate_buffers(dev);
}
示例#2
0
//// 检查磁盘是否更换,如果已更换就使对应高速缓冲区无效。
void
check_disk_change( int dev )
{
	int i;

// 是软盘设备吗?如果不是则退出。
	if( MAJOR( dev ) != 2 )
	{
		return;
	}
// 测试对应软盘是否已更换,如果没有则退出。
	if( !floppy_change( dev & 0x03 ) )
	{
		return;
	}
// 软盘已经更换,所以释放对应设备的i 节点位图和逻辑块位图所占的高速缓冲区;并使该设备的
// i 节点和数据块信息所占的高速缓冲区无效。
	for( i = 0; i < NR_SUPER; i++ )
	{
		if( super_block[i].s_dev == dev )
		{
			put_super( super_block[i].s_dev );
		}
	}
	invalidate_inodes( dev );
	invalidate_buffers( dev );
}
示例#3
0
/*
 * This routine checks whether a floppy has been changed, and
 * invalidates all buffer-cache-entries in that case. This
 * is a relatively slow routine, so we have to try to minimize using
 * it. Thus it is called only upon a 'mount' or 'open'. This
 * is the best way of combining speed and utility, I think.
 * People changing diskettes in the middle of an operation deserve
 * to loose :-)
 *
 * NOTE! Although currently this is only for floppies, the idea is
 * that any additional removable block-device will use this routine,
 * and that mount/open needn't know that floppies/whatever are
 * special.
 */
void check_disk_change(dev_t dev)
{
	int i;
	struct buffer_head * bh;

	switch(MAJOR(dev)){
	case FLOPPY_MAJOR:
		if (!(bh = getblk(dev,0,1024)))
			return;
		i = floppy_change(bh);
		brelse(bh);
		break;

#if defined(CONFIG_BLK_DEV_SD) && defined(CONFIG_SCSI)
         case SCSI_DISK_MAJOR:
		i = check_scsidisk_media_change(dev, 0);
		break;
#endif

#if defined(CONFIG_BLK_DEV_SR) && defined(CONFIG_SCSI)
	 case SCSI_CDROM_MAJOR:
		i = check_cdrom_media_change(dev, 0);
		break;
#endif

#if defined(CONFIG_CDU31A)
         case CDU31A_CDROM_MAJOR:
		i = check_cdu31a_media_change(dev, 0);
		break;
#endif

#if defined(CONFIG_MCD)
         case MITSUMI_CDROM_MAJOR:
		i = check_mcd_media_change(dev, 0);
		break;
#endif

         default:
		return;
	};

	if (!i)	return;

	printk("VFS: Disk change detected on device %d/%d\n",
					MAJOR(dev), MINOR(dev));
	for (i=0 ; i<NR_SUPER ; i++)
		if (super_blocks[i].s_dev == dev)
			put_super(super_blocks[i].s_dev);
	invalidate_inodes(dev);
	invalidate_buffers(dev);

#if defined(CONFIG_BLK_DEV_SD) && defined(CONFIG_SCSI)
/* This is trickier for a removable hardisk, because we have to invalidate
   all of the partitions that lie on the disk. */
	if (MAJOR(dev) == SCSI_DISK_MAJOR)
		revalidate_scsidisk(dev, 0);
#endif
}
示例#4
0
/*
 * This routine checks whether a floppy has been changed, and
 * invalidates all buffer-cache-entries in that case. This
 * is a relatively slow routine, so we have to try to minimize using
 * it. Thus it is called only upon a 'mount' or 'open'. This
 * is the best way of combining speed and utility, I think.
 * People changing diskettes in the middle of an operation deserve
 * to loose :-)
 *
 * NOTE! Although currently this is only for floppies, the idea is
 * that any additional removable block-device will use this routine,
 * and that mount/open needn't know that floppies/whatever are
 * special.
 */
void check_disk_change(int dev)
{
    int i;

    if (MAJOR(dev) != 2)
        return;
    if (!floppy_change(dev & 0x03))
        return;
    for (i=0 ; i<NR_SUPER ; i++)
        if (super_block[i].s_dev == dev)
            put_super(super_block[i].s_dev);
    invalidate_inodes(dev);
    invalidate_buffers(dev);
}
示例#5
0
/*
 * This routine checks whether a floppy has been changed, and
 * invalidates all buffer-cache-entries in that case. This
 * is a relatively slow routine, so we have to try to minimize using
 * it. Thus it is called only upon a 'mount' or 'open'. This
 * is the best way of combining speed and utility, I think.
 * People changing diskettes in the middle of an operation deserve
 * to loose :-)
 *
 * NOTE! Although currently this is only for floppies, the idea is
 * that any additional removable block-device will use this routine,
 * and that mount/open needn't know that floppies/whatever are
 * special.
 */
void check_disk_change(int dev)
{
	int i;
	struct buffer_head * bh;

	if (MAJOR(dev) != 2)
		return;
	if (!(bh = getblk(dev,0)))
		return;
	i = floppy_change(bh);
	brelse(bh);
	if (!i)
		return;
	for (i=0 ; i<NR_SUPER ; i++)
		if (super_block[i].s_dev == dev)
			put_super(super_block[i].s_dev);
	invalidate_inodes(dev);
	invalidate_buffers(dev);
}
示例#6
0
文件: dsk.c 项目: TijmenW/FreeDOS
STATIC WORD play_dj(ddt * pddt)
{
  /* play the DJ ... */
  if ((pddt->ddt_descflags & (DF_MULTLOG | DF_CURLOG)) == DF_MULTLOG)
  {
    int i;
    ddt *pddt2 = getddt(0);
    for (i = 0; i < blk_dev.dh_name[0]; i++, pddt2++)
    {
      if (pddt->ddt_driveno == pddt2->ddt_driveno &&
          (pddt2->ddt_descflags & (DF_MULTLOG | DF_CURLOG)) ==
          (DF_MULTLOG | DF_CURLOG))
        break;
    }
    if (i == blk_dev.dh_name[0])
    {
      put_string("Error in the DJ mechanism!\n");   /* should not happen! */
    }
    else
    {
      xreg dx;
      dx.b.l = pddt->ddt_logdriveno;
      dx.b.h = pddt2->ddt_logdriveno;
      /* call int2f/ax=4a00 */
      if (floppy_change(dx.x) != 0xffff) {
        /* if someone else does not make a nice dialog... */
        template_string[DRIVE_POS] = 'A' + pddt2->ddt_logdriveno;
        put_string(template_string);
        put_string("Insert");
        template_string[DRIVE_POS] = 'A' + pddt->ddt_logdriveno;
        put_string(template_string + 6);
        put_string("Press any key to continue ... \n");
        fl_readkey();
      }
      pddt2->ddt_descflags &= ~DF_CURLOG;
      pddt->ddt_descflags |= DF_CURLOG;
      pokeb(0, 0x504, pddt->ddt_logdriveno);
    }
    return M_CHANGED;
  }
  return M_NOT_CHANGED;
}