22 lines
1.1 KiB
Plaintext
22 lines
1.1 KiB
Plaintext
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# Void Filesystem
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Just a dummy filesystem for learning.
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## Virtual Filesystem (VFS)
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Linux VFS allows us to write customize filesystem. The filesystem must be able to mount, other operations such as file read/write or folder creation/deletion can be customized.
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A filesystem can be virtual, without a backed-up device. This is the case for, I guess, network file descriptors. For filesystem with a backed-up device, usually a block device, the underlying block device can be accessed by sb_bread to read a block.
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Internally, a filesystem must provide a superblock, that will be used as a pointer to read files.
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When a file is read, the inode of the file entry can be accessed. If we also keep the internal data of the file in `inode->i_private`, we can fetch that to read the file system through `sb_read(inode->sb)`.
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## References
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[simplefs](https://github.com/sysprog21/simplefs)
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[Linux Kernel Labs - File system drivers](https://linux-kernel-labs.github.io/refs/heads/master/labs/filesystems_part1.html)
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[Linux Kernel Documentation](https://docs.kernel.org/filesystems/vfs.html)
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