ccw_device_get_ciw(9)

💅 ccw_device_get_ciw(9) — a Kernel API Manual moment

okay so picture this: you're deep in the Kernel API Manual (yes, that's the manual name, we're being official ✨) and you need to find a CIW. Don't panic, bestie, this little function has you covered.

---

🌸 NAME 🌸

ccw_device_get_ciw — literally just search for a CIW command in extended sense data. That's the whole vibe. 🎀

---

✨ SYNOPSIS ✨

struct ciw * ccw_device_get_ciw (struct ccw_device *cdev , __u32 ct );

---

🫶 ARGUMENTS 🫶

• cdev — the ccw device you want to inspect, like, the thing you're snooping on 👀
• ct — the command type you're looking for. that's it. that's the search term 💅

---

💖 DESCRIPTION 💖

so during SenseID (iykyk), command information words — CIWs, iconic acronym, no notes — describing special commands available to the device may have been stored in the extended sense data. 🦋

this function goes searching for CIWs of a specified command type inside that extended sense data. it's giving "find my specific little guy in a pile of little guys." main character search energy, fr fr. 🔥

---

⭐ RETURN ⭐

• NULL — if no extended sense data has been stored, OR if no CIW of the specified command type could be found. sad but valid. 😭
• otherwise — a pointer to the CIW of the specified command type. slay. that's your winner. 👑

---

🌈 SEE ALSO 🌈

the kernel file, for the curious besties:

• ./drivers/s390/cio/device_ops.c

and the whole extended friend group 🧚:

• ccw_device_set_options_mask(9), ccw_device_set_options(9), ccw_device_clear_options(9), ccw_device_is_pathgroup(9), ccw_device_is_multipath(9), ccw_device_clear(9), ccw_device_start_timeout_key(9), ccw_device_start_key(9), ccw_device_start(9), ccw_device_start_timeout(9), ccw_device_halt(9), ccw_device_resume(9), ccw_device_get_path_mask(9), ccw_device_get_chp_desc(9), ccw_device_get_util_str(9), ccw_device_get_id(9), ccw_device_tm_start_timeout_key(9), ccw_device_tm_start_key(9), ccw_device_tm_start(9), ccw_device_tm_start_timeout(9), ccw_device_get_mdc(9), ccw_device_tm_intrg(9), ccw_device_get_schid(9), ccw_device_pnso(9), ccw_device_get_cssid(9), ccw_device_get_iid(9), ccw_device_get_chpid(9), ccw_device_get_chid(9)

---

ok that's the whole page bestie, go get your CIW 💜

and that's a wrap!! brought to you by the source at ./drivers/s390/cio, dropped in October 2026, and filed under ccw_device_get_ciw(9) — mwah, stan forever 🍓🌸💅