> 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/man9/bus_release_resource.9.md).

# bus\_release\_resource.9

`bus_release_resource` — 释放总线上的资源

## 名称

`bus_release_resource`

## 概要

```c
#include <sys/param.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <machine/resource.h>

int
bus_release_resource(device_t dev, struct resource *r)
```

## 描述

释放由 [bus\_alloc\_resource(9)](/man/man9/bus_alloc_resource.9.md) 分配的资源。释放时资源必须不在使用中，即之前要调用适当的函数（例如对于 IRQ 调用 bus\_teardown\_intr(9)）。

* `dev` 是拥有资源的设备。
* `r` 是指向 `struct resource` 的指针，即 [bus\_alloc\_resource(9)](/man/man9/bus_alloc_resource.9.md) 返回的资源本身。

## 返回值

如果设备 `dev` 没有父设备，返回 `EINVAL`，否则返回 `0`。如果无法释放资源，内核将 panic。

## 实例

```c
	/* 停用 IRQ */
	bus_teardown_intr(dev, foosoftc->irqres, foosoftc->irqid);
	/* 释放 IRQ 资源 */
	bus_release_resource(dev, foosoftc->irqres);
	/* 释放 I/O 端口资源 */
	bus_release_resource(dev, foosoftc->portres);
```

## 参见

[bus\_alloc\_resource(9)](/man/man9/bus_alloc_resource.9.md), [device(9)](/man/man9/device.9.md), [driver(9)](/man/man9/driver.9.md)

## 作者

本手册页由 Alexander Langer <alex@big.endian.de> 编写。


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