cp_init(9)

💖 cp_init(9) — Kernel API Manual energy 💖

okay bestie, welcome to the Kernel API Manual page for cp_init(9) — the little function that gets your channel program its ccwchain moment. no cap, let's get into it.

🎀 NAME 🎀

cp_init — allocate ccwchains for a channel program.

✨ SYNOPSIS ✨

int cp_init (struct channel_program *cp , union orb *orb );

🌸 ARGUMENTS 🌸

• cp — the channel_program on which to perform the operation. that's the main character right there.
• orb — the control block for the channel program from the guest.

🦋 DESCRIPTION 🦋

okay so this creates one or more ccwchain(s), and copies the raw data of the target channel program from orb->cmd.iova to the new ccwchain(s). literally the whole vibe.

Limitations:

1. Supports idal(c64) ccw chaining.
2. Supports 4k idaw.

⭐ RETURN ⭐

0 on success and a negative error value on failure. that's it, that's the return lore 💅

🔥 SEE ALSO 🔥

Kernel file ./drivers/s390/cio/vfio_ccw_cp.c — and these absolute icons:

• ccwchain_calc_length(9)
• cp_free(9)
• cp_prefetch(9)
• cp_get_orb(9)
• cp_update_scsw(9)
• cp_iova_pinned(9)

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🫶 cute sign-off: source/version ./drivers/s390/cio, dated October 2026, and the page is cp_init(9). bye bestie, go be iconic with your channel programs 💅✨