Documentation/ide/ide-tape.txt

Chinese translated version of Documentation/filesystems/ecryptfs.txt
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Documentation/ide/ide-tape.txt的中文翻译
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IDE ATAPI streaming tape driver.

IDE ATAPI 的流式磁带驱动程序。

This driver is a part of the Linux ide driver.

此驱动程序是 Linux ide 驱动程序的一部分。

The driver, in co-operation with ide.c, basically traverses the request-list for the block device interface. The character device interface, on the other hand, creates new requests, adds them to the
request-list of the block device, and waits for their completion.

结合了ide.c的驱动程序，基本上遍历了所有块设备接口的请求列表。另一方面，字符设备接口创建了新的请求，并且将它们添加到了块设备的请求列表中，等待其完成。

The block device major and minor numbers are determined from the tape's relative position in the ide interfaces, as explained in ide.c.

块设备的主要和次要编号，是由磁带在 ide 接口上的相对位置决定的，就像 ide.c 所述的那样。

The character device interface consists of the following devices:

字符设备接口包括以下设备：

ht0 major 37, minor 0 first IDE tape, rewind on close.

ht1 major 37, minor 1 second IDE tape, rewind on close.

...

nht0 major 37, minor 128 first IDE tape, no rewind on close.

nht1 major 37, minor 129 second IDE tape, no rewind on close.

...

The general magnetic tape commands compatible interface, as defined by include/linux/mtio.h, is accessible through the character device.

通用的磁带命令了兼容的接口，通过对字符设备的访问，其由include/linux/mtio.h所定义。

General ide driver configuration options, such as the interrupt-unmask flag, can be configured by issuing an ioctl to the block device interface, as any other ide device.

通用 ide 驱动程序的配置选项，如取消中断屏蔽的标志，可以跟其他的ide 设备一样，通过向块设备接口，发出一个ioctl 来实现配置。

Our own ide-tape ioctl's can be issued to either the block device or the character device interface.

我们自己的ide-tape ioctl 可以发给块设备或字符设备接口。

Maximal throughput with minimal bus load will usually be achieved in the following scenario:

在下列情形中，通常可达到，总线能够负载的吞吐量的最大和最小值：

1. ide-tape is operating in the pipelined operation mode.

1. ide-tape正在流水线的操作模式下运行。

2. No buffering is performed by the user backup program.

2.无缓冲是由用户备份程序执行的。

Testing was done with a 2 GB CONNER CTMA 4000 IDE ATAPI Streaming Tape Drive.

2 GB CONNER CTMA 4000 IDE ATAPI 的流出磁带驱动器，进行了测试。

Here are some words from the first releases of hd.c, which are quoted in ide.c and apply here as well:

在hd.c发行的第一版当中，有一些在ide.c中被引用，并且在这里也同样适用的文字：

| Special care is recommended. Have Fun!

|建议特别关注一下。玩得愉快！

Possible improvements:

可能的改进：

1. Support for the ATAPI overlap protocol.

1. ATAPI 重叠协议的支持。

In order to maximize bus throughput, we currently use the DSC overlap method which enables ide.c to service requests from the other device while the tape is busy executing a command. The DSC overlap
method involves polling the tape's status register for the DSC bit, and servicing the other device while the tape isn't ready.

为了最大化总线的吞吐量，我们目前使用的是，当磁带忙于执行一个命令时，可以让 ide.c 在另一台设备上请求提供服务的 DSC 重叠方法。DSC 重叠法涉及到了 DSC 位的磁带状态寄存器的轮询，并且它还可以为其他没有准备好磁带的设备提供服务。

In the current QIC development standard (December 1995), it is recommended that new tape drives will *in addition* implement the ATAPI overlap protocol, which is used for the same purpose - efficient
use of the IDE bus, but is interrupt driven and thus has much less CPU overhead.

在当前的QIC发展标准 （1995 年 12 月） 中，它建议，新的磁带驱动器将 * 在加法 *中实现IDE 总线ATAPI 重叠协议用于相同目的-有效的使用，但由于是中断驱动的，其 CPU的开销较少。

ATAPI overlap is likely to be supported in most new ATAPI devices, including new ATAPI cdroms, and thus provides us a method by which we can achieve higher throughput when sharing a (fast) ATA-2 disk
with any (slow) new ATAPI device.

ATAPI 重叠很可能在最新的 ATAPI 设备，包括新的 ATAPI 光驱中被支持，因此，这样为我们提供了一种方法：通过它，我们可以，在与任何 （慢） 的新 ATAPI 设备共享 (快速) ATA 2 磁盘时，实现更高的吞吐量。

原文地址:http://lxr.linux.no/#linux+v3.11.6/Documentation/ide/ide-tape.txt