decode_from_super_block(9)

📦 version 7.3.1, in nixpkgs unstable

💅 decode_from_super_block — the kernel API manual moment

okay so bestie, you've stumbled into the kernel API manual for decode_from_super_block(9) and honestly? you're in the right place. let's get into it 🫶

✨ NAME ✨

decode_from_super_block — decodes the VDO state from the super block, and then validates that it is actually correct. that's the whole gig. it reads, it checks, it slays 💅

🎀 SYNOPSIS 🎀

int decode_from_super_block (struct vdo *vdo );

one function, one argument, one int coming back at you. no cap.

🌸 ARGUMENTS 🌸

  • vdo — the vdo that is being loaded. that's it. that's the vibe. it's the thing you're loading, and this function is about to go look at its super block 👑

🦋 DESCRIPTION 🦋

okay so here's the tea, and this part is important, like highkey do-not-skip-this important 😭

if this method returns an error, then the component states must be destroyed explicitly. you have to clean them up yourself. nobody's doing it for you. it's giving "you broke it, you fix it" energy 💀

but if this method returns successfully? then the component states must not be destroyed. do not touch them. leave them alone. they're fine. they're thriving. main character energy only 💖

so basically: error → destroy the component states. success → hands off the component states. periodt. get it backwards and that's on you 🙈

⭐ RETURN ⭐

VDO_SUCCESS or an error. that's the whole return situation. iconic, honestly. either it went great or it very much did not 🌈

💜 SEE ALSO 💜

the kernel file is ./drivers/md/dm-vdo/dm-vdo-target.c, and it's surrounded by a whole friend group of functions — here's literally all of them, no cuts, no skips, full lineup ✨

go read them. all of them. iykyk 🔥

that's the page!! tysm for reading bestie, this one came from ./drivers/md/dm-vdo and the version/date stamp on it is October 2026 — so yeah, very much a future-classic 🧚💜 mwah, go decode something 💋

📦 where this page comes from