fs_init.md

Filesystem Initialization

Filesystem initialisation happens whenever the file system is mounted.

Goals

• If it is the first time the filesystem is mounted
  • create root directory
• if the filesystem had been mounted before
  • update the last_mounted_at property

Non Goals

• Adding default files in the default directory
• Using A BTree to store directory entries

Design

Implementation

struct Directory {
    entries HashMap<string, i32>
}

1. Check if the first inode bitmap has been allocated
2. If it has, that means that a root directory exists.
    1. Just update the last_mounted_at property
3. If there's no root directory
    1. Create a directory inode entry
    2. Mark the inode's bitmap as allocated
    3. Save the directory