nilfs_ioctl_get_info(9)

📦 version 7.3.1, in nixpkgs unstable

💫 nilfs_ioctl_get_info(9) 💫

okay so bestie, we're in the Kernel API Manual today and this is the page for nilfs_ioctl_get_info — yes that name is a mouthful, yes it's iconic, we move.

🌸 NAME 🌸

nilfs_ioctl_get_info — the wrapping function of get metadata info. that's it, that's the whole vibe: it's the little handler that goes and gets you metadata info. 🎀

✨ SYNOPSIS ✨

int nilfs_ioctl_get_info (struct inode *inode , struct file *filp ,
       unsigned int cmd , void __user *argp , size_t membsz , ssize_t
       (*dofunc)(struct the_nilfs *, __u64 *, int, void *, size_t, size_t) );

look at that signature. she's long. she's gorgeous. she takes a function pointer. main character energy fr fr. 💅

🦋 ARGUMENTS 🦋

  • inode — the inode object. you know her, you love her. 🫶
  • filp — the file object. hi bestie.
  • cmd — the ioctl's request code. this is the "what do you actually want" part.
  • argp — a pointer on the argument from userspace. this is where the good stuff lands. ✨
  • membsz — size of an item in bytes. numbers, we love numbers.
  • dofunc — the concrete function of getting metadata info. like, the actual worker bee that does the thing. 🐝

🌈 DESCRIPTION 🌈

so nilfs_ioctl_get_info gets metadata info by means of calling the dofunc function. it's a wrapper, it's a delegator, it's giving project manager who actually does the work... no wait, it does the work, dofunc does the work. either way, teamwork makes the dream work. 💖

the requested metadata information is copied to userspace memory argp. so whatever you asked for? it goes right back out to you. slay. 🎀

🔥 RETURN 🔥

0 on success, or one of the following negative error codes on failure. no in-between, she's very decisive:

  • -EFAULT — failure during execution of requested operation. 😭
  • -EINVAL — invalid arguments from userspace. bestie. come on. read the args.
  • -EIO — I/O error. the disk had a moment. 💀
  • -ENOMEM — insufficient memory available. not enough room, the vibe check failed.

👑 SEE ALSO 👑

start with the kernel file ./fs/nilfs2/ioctl.c — that's the actual hometown of all of these:

okay that's the whole friend group, go say hi to all of them. iykyk. 🌟

and that's the page, bestie!! this one lives in ./fs/nilfs2, dated October 2026 — yes, the future, we're ahead of the timeline, periodt. 💜🦋✨

📦 where this page comes from