STRUCT XA_LIMIT(9)

📦 version 7.3.1, in nixpkgs unstable

💅 struct xa_limit(9) — like, the whole manual, bestie

okay so first things first: this is a page out of the Kernel API Manual, and the star of the show is struct xa_limit. it lives in the kernel, it's fancy, it's giving "ID bouncer at the club" energy. let's get into it 🫶

✨ NAME ✨

struct xa_limit — literally just represents a range of IDs. that's it. that's the whole vibe. 🎀

🌸 SYNOPSIS 🌸

struct xa_limit {
    u32 max;
    u32 min;
 };

yes bestie, that's the entire struct. two little u32s and a dream. 💖

🦋 Members 🦋

  • max — the maximum ID you're allowed to allocate, and it's inclusive (so like, max itself gets an invite to the party too, no cap).
  • min — the lowest ID you're allowed to allocate, also inclusive (yes min is invited as well, it's only fair ✨).

👑 DESCRIPTION 👑

so the way this works: this structure gets used either directly or via the XA_LIMIT macro to communicate the range of IDs that are valid for allocation. that's its whole job and it does it slayfully. 💅

and here's the good part — three common ranges are already predefined for you, no assembly required:

  • xa_limit_32b — [0 - UINT_MAX]
  • xa_limit_31b — [0 - INT_MAX]
  • xa_limit_16b — [0 - USHRT_MAX]

three little presets, all iconic, all just sitting there waiting for you. 🔥

🔍 SEE ALSO 🔍

okay this next part is a lot but we don't skip, we don't scroll past, we read every single one. it's all in the kernel file ./include/linux/xarray.h, and honestly the whole xarray friend group showed up:

like I said. everyone came. 🧚

ngl bestie, remember the inclusive thing on min and max — both endpoints get allocated, that's the whole point of the range 🍓

and that's the page!! sourced from ./include/linux, dated October 2026, and published under the struct xa_limit(9) banner in the Kernel API Manual 💜 go read your xarray docs, ily, bye!! 🌈⭐

📦 where this page comes from