rt thread 文件系统dfs挂载2个块设备

发布于 2025-06-24 10:30:07 浏览：62 订阅该版

[tocm]

# 挂载多个块设备

挂载需求：**将sd卡挂载在根目录`/`下，将fal的log分区挂载在`/flash`目录下**

1. 利用sfud初始化nor flsh
2. 初始化fal，这里将nor flash划分为2个分区，将其中的log分区注册为一个块设备
3. 需要先挂载sd卡到`/`目录下
4. 继续挂载log块设备在目录`/flash`目录下

## 1.注册spi从设备

![screenshot_image-20250623185110631.png](https://oss-club.rt-thread.org/uploads/20250624/9da8d61955044dafe65d0c2031619f75.png.webp)

## 分为2个分区

>rt-thread\components\fal\inc\fal_cfg.h

![screenshot_image-20250623184955481.png](https://oss-club.rt-thread.org/uploads/20250624/adc5f4d1066d91171c1bdc1add479027.png.webp)

## 注册块设备

![screenshot_image-20250623185216546.png](https://oss-club.rt-thread.org/uploads/20250624/5276580867ec4b4ef7338c44d85de1c1.png.webp)

## 使能文件系统挂载列表

![screenshot_image-20250623154522875.png](https://oss-club.rt-thread.org/uploads/20250624/e4578775ec5eec340530a2604a944408.png)

## 用户自定义一个挂载列表

```c
#ifdef RT_USING_DFS_MNTTABLE
const struct dfs_mount_tbl mount_table[] =
    {
        {"sd0", "/", "elm", 0, 0},      // 将sd0挂载在根目录下
        {"log", "/flash", "elm", 0, 0}, /**将log块设备挂载在/falsh目录下 */
        {0}};

#include <dfs_fs.h>
```

## 添加一个指令查看磁盘信息

```c
void show_disk_info(const char *path)
{
    struct statfs buf;

if (dfs_statfs(path, &buf) == 0)
    {
        rt_uint64_t total = (rt_uint64_t)buf.f_blocks * buf.f_bsize;
        rt_uint64_t free = (rt_uint64_t)buf.f_bfree * buf.f_bsize;
        rt_kprintf("%s: Total=%0.1f MB, Free=%0.1f MB\n",
                   path, total / 1024.0f / 1024.0f, free / 1024.0f / 1024.0f);
    }
}

void show_disk(void)
{
    show_disk_info("/");
    show_disk_info("/flash");
}
MSH_CMD_EXPORT(show_disk, show_disk info and num);
```

查看磁盘信息

>msh />
>msh />show_disk
>/: Total=3781.0 MB, Free=3766.7 MB
>/flash: Total=10.0 MB, Free=7.8 MB
>msh />

![screenshot_image-20250623184423810.png](https://oss-club.rt-thread.org/uploads/20250624/71aad5fe5c688516ecfa63c0d014aeef.png)

从此之后在`/flash`目录下的所有操作都是对nor flash的读写，非`/flash`操作就在sd卡中

如需源码移步 
[rt thread 挂载2个块设备](https://blog.csdn.net/u010261063/article/details/148862508?sharetype=blogdetail&sharerId=148862508&sharerefer=PC&sharesource=u010261063&spm=1011.2480.3001.8118)