may_umount(9)

📦 version 7.3.1, in nixpkgs unstable

💅 may_umount(9) — kernel API manual, bestie edition 🎀

okay so real talk, this is from the Kernel API Manual and it's the page for may_umount, and honestly? she's a little icon. let's get into it ✨

🌸 NAME 🌸

may_umount — check if a mount point is busy

like, is anybody using this thing or can we pack it up 👀

✨ SYNOPSIS ✨

int may_umount (struct vfsmount *mnt );

yes bestie that's the whole signature, no notes 💅

🦋 ARGUMENTS 🦋

  • mnt — the root of the mount. the mount-y-est mount. the one we're vibing about 🫶

💖 DESCRIPTION 💖

so this one gets called to check if a mount point has, like, anything going on with it — any open files, pwds, chroots, or sub mounts. if literally any of those are hanging around, she's busy, no cap.

and here's the part you gotta know: if the mount has sub mounts, this will return busy regardless of whether the sub mounts themselves are busy. like, it doesn't even check. sub mount exists = busy = periodt. 💀

also it doesn't take quota and stuff into account — IOW, in some cases it will give false negatives 🙈 so don't treat it like gospel, okay?

the main reason why it's here at all is that we need a non-destructive way to look for easily umountable filesystems. she's not out here wrecking anything, she's just doing a vibe check on your mounts. main character energy, genuinely 🔥

ngl, the "false negatives" thing is a real caveat — this is a check, not a guarantee. act accordingly bestie 🎀

👑 SEE ALSO 👑

Kernel file ./fs/namespace.c and her whole friend group:

and that's the page!! 🍓 this lil beauty lives in ./fs, dated October 2026 — go off, October 2026, you ate 🌈⭐ mwah 💜

📦 where this page comes from