cio_tm_start_key(9)

💅 cio_tm_start_key(9) — Kernel API Manual ✨

okay bestie, welcome to the glow-up of cio_tm_start_key(9) — a little kernel API page from the Kernel API Manual, and honestly it's serving main character energy in the s390/cio world 🎀

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🌸 NAME 🌸

cio_tm_start_key — literally just performs the start function, no cap 💖

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✨ SYNOPSIS ✨

int cio_tm_start_key (struct subchannel *sch , struct tcw *tcw , u8 lpm
, u8 key );

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🦋 ARGUMENTS 🦋

• sch — the subchannel on which to perform the start function. like, that's the stage, and it's the main character's stage 🫶
• tcw — the transport-command word to be started. the actual thing we're launching, slay 💅
• lpm — mask of paths to use. yes, a mask, and yes, it's giving mysterious but essential ✨
• key — storage key to use for storage access. it's the key, iykyk 🔑

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🧚 DESCRIPTION 🧚

Start the tcw on the given subchannel. That's it, that's the vibe 💖

It returns zero on success, and non-zero otherwise. so fr fr, check your return value — zero is the slay outcome, anything else means it's not giving 😭

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👑 SEE ALSO 👑

Kernel file ./drivers/s390/cio/cio.c, plus these iconic friends you should also go read:

• cio_cancel_halt_clear(9)
• cio_update_schib(9)
• cio_enable_subchannel(9)
• cio_disable_subchannel(9)
• cio_tm_intrg(9)

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and that's the whole page, periodt 💜 this little beauty lives in ./drivers/s390/cio and it's stamped October 2026 — so go forth, start your tcw, and stan the return code 🌈💅