libnvme(2)

💖 libnvme(2) — API Manual 💖

okay bestie, welcome to the libnvme manual, page 2 ofc, and today's main character is a lil struct called struct nvme_registered_ctrl 🎀 she's literally the Registered Controller Data Structure and she is coming through to spill all her fields. no cap, every byte matters here, so let's get into it ✨

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🌸 NAME 🌸

struct nvme_registered_ctrl — Registered Controller Data Structure 👑

like. the whole vibe of this page is this one struct. that's it. that's the page. and honestly? iconic.

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🦋 SYNOPSIS 🦋

here she is in all her glory, copy it exactly bestie, don't you dare retype it by hand 🙈

struct nvme_registered_ctrl {
    __le16 cntlid;
    __u8 rcsts;
    __u8 rsvd3[5];
    __le64 hostid;
    __le64 rkey;
 };

look at her. little endian, nicely packed, reserved bytes doing their reserved little thing. we love a tidy memory layout 💅

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✨ Members ✨

okay so each field is a whole personality, let me introduce you properly 🫶

• cntlid — Controller ID. that's her whole name tag basically 💖
• rcsts — Reservation Status. the vibe check of the reservation, if you will ✨
• rsvd3 — Reserved. she's just holding space 🕯️ do not touch, do not question, do not dream about her.
• hostid — Host Identifier</hostid>. who's this host? mystery solved, it's right there 🦋
• rkey — Reservation Key. the key. for the reservation. the way that this is exactly what it sounds like 😭🔥

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ngl bestie, rsvd3 being reserved means reserved — that's not a suggestion, that's a boundary. respect the padding 🎀

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and that's the whole page, periodt 💅 thanks for reading my little struct essay, mwah 🫶

✨ sign-off time ✨ this absolute gem dropped in July 2026 as part of the API Manual, filed under libnvme(2) alongside struct nvme_registered_ctrl herself. go forth and register your controllers responsibly, bestie 🌸💜