mei_ext_begin(9)

🦋 mei_ext_begin(9) 🦋

okay so bestie, we're in the Kernel API Manual today and this one is literally a function from the kernel, no cap. It's called mei_ext_begin and it's giving "start of the list" energy. Let's get into it 💅

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✨ NAME ✨

mei_ext_begin — extended header iterator begin 🎀

Like, it's the beginning-of-the-iterator girlie for extended headers. She's the first one at the party, she opens the door, etc etc.

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🌸 SYNOPSIS 🌸

struct mei_ext_hdr * mei_ext_begin (struct mei_ext_meta_hdr *meta );

copy that exactly please, character for character, don't be weird about the spacing 🙈

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💖 ARGUMENTS 💖

• meta — the meta header of the extended header list. yep that's the whole vibe. she's the meta header, she holds the list, that's her job and she's slaying it 👑

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⭐ RETURN ⭐

The first extended header 🫶

that's it. that's the return. the first one. if you were hoping for the second one, that's a different function, bestie (see below 👀)

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🔥 SEE ALSO 🔥

okay this list is long long, but every single one is iconic in her own way so we're doing all of them, no skipping, periodt 💀

Kernel file:

• ./drivers/misc/mei/hw.h

The enums and structs and friends, in order, exactly as they appear:

• enum mei_hbm_status(9)
• enum mei_ext_hdr_type(9)
• struct mei_ext_hdr(9)
• struct mei_ext_meta_hdr(9)
• struct mei_ext_hdr_vtag(9)
• mei_ext_last(9)
• struct mei_ext_hdr_gsc_h2f(9)
• struct mei_ext_hdr_gsc_f2h(9)
• mei_ext_next(9)
• mei_ext_hdr_len(9)
• struct mei_msg_hdr(9)
• struct mei_hbm_cl_cmd(9)
• enum hbm_host_enum_flags(9)
• struct hbm_host_enum_request(9)
• struct mei_client_properties(9)
• struct hbm_add_client_request(9)
• struct hbm_add_client_response(9)
• struct hbm_power_gate(9)
• struct hbm_client_connect_request(9)
• struct hbm_client_connect_response(9)
• struct hbm_notification_request(9)
• struct hbm_notification_response(9)
• struct hbm_notification(9)
• struct hbm_dma_mem_dscr(9)
• struct hbm_dma_setup_request(9)
• struct hbm_dma_setup_response(9)
• struct hbm_dma_ring_ctrl(9)
• struct hbm_capability_request(9)
• struct hbm_capability_response(9)
• struct hbm_client_dma_map_request(9)
• struct hbm_client_dma_unmap_request(9)
• struct hbm_client_dma_response(9)

like I said. a lot. but we ate and left no crumbs 🍓

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ok real talk: mei_ext_begin gets you the first header, mei_ext_next walks you forward, and mei_ext_last tells you when you've hit the end. the whole squad, iykyk 🧚

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and that's the page!! this one lives at ./drivers/misc/mei in the tree, it's dated October 2026, and it's filed under mei_ext_begin(9) — mwah, go read the rest of the MEI docs, ilysm 💜✨🌈