> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/man/man4/usfs.4.md).

# usfs.4

`usfs` — USB 设备端仅批量传输大容量存储支持

## 名称

`usfs`

## 概要

要将此驱动编译进内核，请将以下行加入你的内核配置文件：

> device usb device usfs

或者，要在引导时以模块方式加载该驱动，请将以下行加入 loader.conf(5)：

```sh
usfs_load="YES"
```

## 描述

**此驱动已过时。建议用户改用** [**cfumass(4)**](/man/man4/cfumass.4.md)**。**

`usfs` 驱动在 USB 协议栈以 USB 设备端模式激活时（加载 [usb\_template(4)](/man/man4/usb_template.4.md) 模块并将 `hw.usb.template` sysctl 设置为 0）提供 USB 大容量存储设备仿真支持。

附加时，该驱动会创建一个可读写的 RAM 磁盘。

## 参见

[cfumass(4)](/man/man4/cfumass.4.md), [umass(4)](/man/man4/umass.4.md), [usb(4)](/man/man4/usb.4.md), [usb\_template(4)](/man/man4/usb_template.4.md)

## 历史

`usfs` 驱动出现于 FreeBSD 8.0。


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