zfcp_diag_u...ffer_limited(9)

📦 version 7.3.1, in nixpkgs unstable

💅 zfcp_diag_update_buffer_limited(9) — the rate-limited glow-up

okay so bestie, welcome to the Kernel API Manual ✨ this one is zfcp_diag_update_buffer_limited(9) and it's literally the "collect the diagnostics but, like, chill" function. no cap.

✨ SYNOPSIS ✨

int zfcp_diag_update_buffer_limited (struct zfcp_adapter *const adapter
, struct zfcp_diag_header *const hdr , zfcp_diag_update_buffer_func
buffer_update );

look at her. so clean. so structured. 🎀

🌸 ARGUMENTS 🌸

  • adapter — the Adapter we're pulling the diagnostics from. that's the source of truth, bestie 🫶
  • hdr — the buffer-header that's getting updated with all those collected diagnostics. she's the one receiving the makeover 💅
  • buffer_update — the Specific implementation for actually collecting and updating. iykyk — this is the part that does the real work 🔥

💖 DESCRIPTION 💖

okay so here's the tea ☕ — this function causes an update of the given hdr by calling the also-given buffer_update function. that's the whole vibe.

but wait, because if multiple sources call this at the same time, it synchronizes the update for you: only one source is allowed to call buffer_update, and the others just wait for that source to complete instead. and bestie, the wait is interruptible — we love an exit strategy 🌈

on top of all that, this version is rate-limited 🧚 and it will only exit if either:

  • the buffer is fresh enough (within the limit) — and honestly if the buffer is fresh enough to begin with, it will do nothing at all, iconic behavior tbh 💀
  • or the source/thread that started this update is the one that made the update — this is the anti-endless-loop protection, periodt 🔁

👑 RETURN 👑

  • 0 — if the update was successfully published and/or the buffer is fresh enough. slay ✨
  • -EINTR — if the thread went into the wait-state and was interrupted. rude but valid 😭
  • whatever buffer_update returns — bestie said "you get what you give" 🫶

⭐ SEE ALSO ⭐

Kernel file ./drivers/s390/scsi/zfcp_diag.c, plus the whole friend group:

💜 reminder: keep every flag, every arg, every return value exactly as-is. the vibes are new, the facts are untouched. fr fr.

okay that's the page!! this gem lives in ./drivers/s390/scsi, and the October 2026 edition is officially signed off — stay fresh, stay rate-limited, and don't forget to interrupt your waits responsibly 🦋💖🎀

📦 where this page comes from