STRUCT SCU_UNSOLICITED_FRAME_HEADER(9)

🦋 struct scu_unsolicited_frame_header(9) 🦋

okay so bestie, we're looking at struct scu_unsolicited_frame_header today — a kernel API manual moment, and honestly? iconic. this is from the Kernel API Manual, section 9, and it's giving "silicon architecture spilled its tea and we wrote it down" energy. let's get into it 🫶

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✨ SYNOPSIS ✨

here's the whole shape of her, no notes, exactly as written:

struct scu_unsolicited_frame_header {
    u32 iit_exists:1;
    u32 protocol_type:3;
    u32 is_address_frame:1;
    u32 connection_rate:4;
    u32 reserved:23;
    u32 data[SCU_UNSOLICITED_FRAME_HEADER_DATA_DWORDS];
};

bitfields everywhere, u32 all the way down, reserved:23 doing absolutely nothing but holding space like a very patient friend 💀 and then data[] sized by SCU_UNSOLICITED_FRAME_HEADER_DATA_DWORDS because why hardcode when a macro can do it for you 💅

💅 Members 💅

ngl, the Members section on this page is literally just vibing there with zero member descriptions attached — that's the whole bit. no cap, that's what's in the source. so the field names up in the synopsis are all we get, and we're not out here inventing lore. respect the source ✨

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🌸 DESCRIPTION 🌸

okay so real talk: this structure delineates the format of an unsolicited frame header. that's the job. that's what she does.

the first DWORD is the UF attributes, and those are defined by the silicon architecture — so like, not us, not the driver, the hardware itself decided that. we're just matching the fit 🔥

the data is the actual header information received on the link. so: attributes first, then the real payload the link handed us. memo received, bestie 🎀

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🔥 SEE ALSO 🔥

go read these next, iykyk:

• Kernel file ./drivers/scsi/isci/unsolicited_frame_control.h — the header's header, main character energy
• enum unsolicited_frame_state(9)
• struct sci_unsolicited_frame(9)
• struct sci_uf_header_array(9)
• struct sci_uf_buffer_array(9)
• struct sci_uf_address_table_array(9)
• struct sci_unsolicited_frame_control(9)

that's the whole friend group right there — read them in order or don't, they're all linked in spirit 🌈

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and that's the page!! struct delivered, bits counted, vibes immaculate 💖

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little sign-off for the credits girlies: this beauty lives over in ./drivers/scsi/isci, and it's dated October 2026 — so yes, she's from the future, and yes she still formats her frame headers perfectly. slay, honestly 👑🍓