fscrypt_prepare_setflags(9)

📦 version 7.3.1, in nixpkgs unstable

✨ fscrypt_prepare_setflags(9) ✨

okay bestie, welcome to the Kernel API Manual 💅 this one's a kernel function in the fscrypt squad, and honestly? she's short but she's important.

🎀 NAME 🎀

fscrypt_prepare_setflags — the little prep step you run before you go changing flags with FS_IOC_SETFLAGS 🦋

🫶 SYNOPSIS 🫶

int fscrypt_prepare_setflags (struct inode *inode , unsigned int
       oldflags , unsigned int flags );

like, that's the whole signature. no cap. ✨

🌸 ARGUMENTS 🌸

  • inode — the inode on which flags are being changed 👑 that's your main character right there
  • oldflags — the old flags 🍓 the before pic
  • flags — the new flags 🌈 the after pic

💖 DESCRIPTION 💖

so here's the vibe check: the caller should be holding i_rwsem for write. 🔥

that's it. that's the whole description. but do not sleep on it — if you're calling this without holding i_rwsem for write, you're not slaying, you're just doing too much 😭 lock it down first, then call, periodt.

⭐ RETURN ⭐

0 on success 🎉 — iconique, we love a clean return.

-errno if the flags change isn't allowed, or if another error occurs 💀 so yeah, if it comes back negative, something said "no ma'am" — check your errno, bestie, it's giving diagnostic clues 🙈

🧚 SEE ALSO 🧚

Kernel file ./fs/crypto/hooks.c and the whole friend group:

go read them, iykyk 💜

lowkey reminder: hold that i_rwsem for write before you call. fr fr. 🫶

and that's the page!! brought to you by the <rainbow>./fs/crypto</rainbow> girlies, October 2026 edition 🌸 mwah, go forth and set those flags responsibly 💅✨

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