STRUCT QAOB(9)

✨ NAME ✨

struct qaob — the queue asynchronous operation block, bestie 💅

So this is a struct from the Kernel API Manual (that's the manual name, cutie, consider it folded in 🎀) and it lives in the kernel headers — it's the block that carries an async QDIO operation's results and storage-block info. Lowkey iconic. Periodt.

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🌸 SYNOPSIS 🌸

struct qaob {
    u64 res0[6];
    u8 res1;
    u8 res2;
    u8 res3;
    u8 aorc;
    u8 flags;
    u16 cbtbs;
    u8 sb_count;
    dma64_t sba[QDIO_MAX_ELEMENTS_PER_BUFFER];
    u16 dcount[QDIO_MAX_ELEMENTS_PER_BUFFER];
    u64 user0;
    u64 res4[2];
    u8 user1[16];
 };

Like, that's the whole shape of it. Every field, every type, every array size — exactly as written, no cap 🫶

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🦋 Members 🦋

Okay so here's the member-by-member vibe check, one bullet each, nothing skipped:

• res0 — reserved parameters 🙈 (yes, plural, it's a u64[6])
• res1 — reserved parameter
• res2 — reserved parameter
• res3 — reserved parameter
• aorc — asynchronous operation return code 🔥 this is the one that tells you how the async op went
• flags — internal flags
• cbtbs — control block type
• sb_count — number of storage blocks
• sba — storage block element addresses (it's a dma64_t array sized QDIO_MAX_ELEMENTS_PER_BUFFER, fyi)
• dcount — size of storage block elements (a u16 array, same QDIO_MAX_ELEMENTS_PER_BUFFER sizing)
• user0 — user definable value ⭐
• res4 — reserved parameter
• user1 — user definable value 💜

So yeah — the reserved ones are just taking up space, don't touch them, and the user* ones are literally yours to play with ✨

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💖 SEE ALSO 💖

Kernel file ./arch/s390/include/asm/qdio.h — and the whole friend group:

• struct qdesfmt0(9)
• struct qdr(9)
• struct qib(9)
• struct slibe(9)
• struct slib(9)
• struct qdio_buffer_element(9)
• struct qdio_buffer(9)
• struct sl_element(9)
• struct sl(9)
• struct slsb(9)
• struct qdio_initialize(9)

Go read those too, bestie, they're all in the same header and they all know each other. Iykyk 🧚

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Okay that's the whole page, mwah 💋 — this one ships from ./arch/s390/include/asm, dated October 2026, under the title struct qaob(9). Slay, bye! 👑🌈