libnvme(9)

💅 libnvme — section 9, bestie ✨

Okay so real quick, this page lives in the libnvme(9) manual — section 9, the big-brain kernel/API shelf — and it's all about one very specific little enum. Buckle up 🎀

---

🌸 NAME 🌸

enum nvme_cmbloc — literally the field that tells you the controller memory buffer location, and no I'm not kidding, that's the whole vibe. It's giving "where in memory does the CMB live" energy 💖

---

✨ SYNOPSIS ✨

Here's the whole enum, in all its glory, copied exactly because I would never do you dirty like that:

enum nvme_cmbloc {
    NVME_CMBLOC_BIR_SHIFT ,
    NVME_CMBLOC_CQMMS_SHIFT ,
    NVME_CMBLOC_CQPDS_SHIFT ,
    NVME_CMBLOC_CDPLMS_SHIFT ,
    NVME_CMBLOC_CDPCILS_SHIFT ,
    NVME_CMBLOC_CDMMMS_SHIFT ,
    NVME_CMBLOC_CQDA_SHIFT ,
    NVME_CMBLOC_OFST_SHIFT ,
    NVME_CMBLOC_BIR_MASK ,
    NVME_CMBLOC_CQMMS_MASK ,
    NVME_CMBLOC_CQPDS_MASK ,
    NVME_CMBLOC_CDPLMS_MASK ,
    NVME_CMBLOC_CDPCILS_MASK ,
    NVME_CMBLOC_CDMMMS_MASK ,
    NVME_CMBLOC_CQDA_MASK ,
    NVME_CMBLOC_OFST_MASK

};

Like, look at her. Eight shifts, eight masks, perfectly balanced 🔥

---

🦋 Constants 🦋

Bestie, here's the thing: every field has a SHIFT (how far to move the bits, iykyk) and a MASK (how to scoop the bits back out). Two halves of one iconic whole 💅

🌈 The SHIFT girlies 🌈

• NVME_CMBLOC_BIR_SHIFT — the shift amount you use to get the base indicator register 👑
• NVME_CMBLOC_CQMMS_SHIFT — shift amount to get the CMB queue mixed memory support flag ✨
• NVME_CMBLOC_CQPDS_SHIFT — shift amount to get the CMB queue physically discontiguous support flag, say that five times fast 😭
• NVME_CMBLOC_CDPLMS_SHIFT — shift amount to get the CMB data pointer mixed locations support flag 🫶
• NVME_CMBLOC_CDPCILS_SHIFT — shift amount to get the CMB data pointer and command independent locations support flag, absolute mouthful, but slay 💀
• NVME_CMBLOC_CDMMMS_SHIFT — shift amount to get the CMB data metadata mixed memory support flag 🌸
• NVME_CMBLOC_CQDA_SHIFT — shift amount to get the CMB queue dword alignment ⭐
• NVME_CMBLOC_OFST_SHIFT — shift amount to get the offset 🎀

---

💖 The MASK icons 💖

• NVME_CMBLOC_BIR_MASK — mask to get the base indicator register 🌈
• NVME_CMBLOC_CQMMS_MASK — mask to get the CMB queue mixed memory support ✨
• NVME_CMBLOC_CQPDS_MASK — mask to get the CMB queue physically discontiguous support 💅
• NVME_CMBLOC_CDPLMS_MASK — mask to get the CMB data pointer mixed locations support 🫶
• NVME_CMBLOC_CDPCILS_MASK — mask to get the CMB data pointer and command independent locations support 🦋
• NVME_CMBLOC_CDMMMS_MASK — mask to get the CMB data metadata mixed memory support 🌸
• NVME_CMBLOC_CQDA_MASK — mask to get the CMB queue dword alignment ⭐
• NVME_CMBLOC_OFST_MASK — mask to get the offset 🎀

Not me hyping up bit manipulation at 2am — but honestly? Shift first, mask second, and you'll never fumble the field extraction. That's the whole trick, no cap 💜

---

Sign-off time, because every icon needs her credits: this page is enum nvme_cmbloc, dated October 2026, and it's part of libnvme(9). Periodt. 🌈👑