register_filesystem(9)

register_filesystem(9) 🦋

okay so this is the Kernel API Manual entry for register_filesystem(9), and bestie, it's giving “tiny function, big main character energy.” Let's get into it 💅✨

📛 NAME

register_filesystem — register a new filesystem 🎀

🛠️ SYNOPSIS

int register_filesystem (struct file_system_type *fs );

🎀 ARGUMENTS

• fs — the file system structure. That's the whole argument list, periodt 💖

💅 DESCRIPTION

okay so register_filesystem adds the file system passed to it to the list of file systems the kernel is aware of for mount and other syscalls. It's literally putting your filesystem on the kernel's radar, and honestly? Obsessed for you ✨

Returns 0 on success, or a negative errno code on an error. No cap, the return situation is simple: 0 means slay, a negative errno code means something went sideways 😭

The struct file_system_type that is passed is linked into the kernel structures and must not be freed until the file system has been unregistered. Not me being dramatic, but this is a hard rule: do not free that struct early. Wait until it's unregistered, iykyk 🫶

fr fr bestie, that “must not be freed” part is not a vibe suggestion — it's the rule 💀

👀 SEE ALSO

• Kernel file ./fs/filesystems.c
• unregister_filesystem(9)

cute little sign-off: this page comes from source/version ./fs, dated October 2026, and it's the register_filesystem(9) manual page. Love that for us, bye bestie 💖🎀✨