STRUCT ESW1(9)

💅 struct esw1(9) — the Kernel API Manual, but make it cute ✨

okay so bestie, welcome to struct esw1 — it's the Format 1 Extended Status Word, aka ESW for short. That's the whole name section, no notes, she's serving concise icon energy 💅

This page lives in the Kernel API Manual (section 9), so like… kernel-internals territory. Buckle up 🎀

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🌸 SYNOPSIS 🌸

Here's the whole struct, and yes you're getting it verbatim because we do not mess with code in this house 🫶

struct esw1 {
    __u8 zero0;
    __u8 lpum;
    __u16 zero16;
    struct erw erw;
    __u32 zeros[3];
 };

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✨ Members ✨

okay so member by member, here's the tea 🍓

• zero0 — reserved zeros. literally just zeros doing their little reserved thing 🙈
• lpum — the last path used mask ⭐
• zero16 — reserved zeros again, she's back for round two 💀
• erw — the extended report word 🔥
• zeros — three fullwords of zeros. that's it. three of them. no cap 👑

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🌈 SEE ALSO 🌈

go read these next, bestie — iykyk 💜

Kernel file ./arch/s390/include/asm/cio.h, plus:

• struct ccw1(9)
• struct ccw0(9)
• struct erw(9)
• struct erw_eadm(9)
• struct sublog(9)
• struct esw0(9)
• struct esw2(9)
• struct esw3(9)
• struct esw_eadm(9)
• struct irb(9)
• struct ciw(9)
• struct ccw_dev_id(9)
• ccw_dev_id_is_equal(9)
• pathmask_to_pos(9)

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bestie that's the whole page, she's short and she ate 💅✨

okay byeee — this one's brought to you by the source path ./arch/s390/include/asm and dated October 2026, and it signs off as struct esw1(9) 🦋🎀💖