tb_ring_alloc_tx(9)

💅 tb_ring_alloc_tx 💅

Okay so bestie, welcome to the Kernel API Manual — yes we're in kernel-land now, and this one is literally all about grabbing yourself a DMA ring so your Thunderbolt stuff can transmit. Iconic. Let's go 🦋

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✨ NAME ✨

tb_ring_alloc_tx — allocate a DMA ring for transmit 🎀

🌸 SYNOPSIS 🌸

struct tb_ring * tb_ring_alloc_tx (struct tb_nhi *nhi , int hop , int
size , unsigned int flags );

Like, that's the whole vibe. You hand it an NHI, a hop, a size and some flags, and it hands you back a struct tb_ring *. Simple as 🫶

💜 ARGUMENTS 💜

• nhi — a pointer to the NHI that the ring is gonna be allocated for. It's giving "here's where my ring lives" 🏠
• hop — the HopID (that's the ring, bestie) you want to allocate ✨
• size — how many entries go in the ring. Pick a number, any number (okay, pick a sensible one) 🔢
• flags — the flags for the ring. Flags!! Everybody loves flags 🚩

🦋 RETURN 🦋

You get a pointer to struct tb_ring 💖 — or NULL otherwise, and no cap, NULL means it did not work out 😭

⭐ SEE ALSO ⭐

Kernel file ./drivers/thunderbolt/nhi.c — that's the main character file right there 👑

Also go read these, fr fr:

• tb_ring_poll(9)
• tb_ring_poll_complete(9)
• tb_ring_alloc_rx(9)
• tb_ring_start(9)
• tb_ring_flush(9)
• tb_ring_stop(9)
• tb_ring_throttling(9)
• nhi_mailbox_cmd(9)
• nhi_mailbox_mode(9)

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Lowkey the whole ring lifecycle is in that list — alloc, start, poll, flush, stop, throttle. Do yourself a favour and read them together, iykyk 💀

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And that's a wrap, bestie 🎀 this little gem lives in ./drivers/thunderbolt and the version vibes are dated October 2026 — slay, go allocate your rings responsibly 💅✨