_dat_walk_gfn_range(9)

📦 version 7.3.1, in nixpkgs unstable

🦋 NAME 🦋

okay so welcome to the _dat_walk_gfn_range(9) page from the Kernel API Manual, bestie — today we're learning how to walk DAT tables 💅 like literally just strolling through them, page frame by page frame, no cap

✨ SYNOPSIS ✨

long _dat_walk_gfn_range (gfn_t start , gfn_t end , union asce asce ,
const struct dat_walk_ops *ops , int flags , void *priv );

that's the whole signature, copy it exactly, do not freestyle it 🙈

🎀 ARGUMENTS 🎀

  • start — the first guest page frame that gets walked. your starting point, your main character entrance 👑
  • end — the guest page frame immediately after the last one to walk. so like, it's exclusive — it's the one right after the finish line, not the finish line itself 🏁
  • asce — the ASCE of the guest mapping. yes queen, that ASCE 🫶
  • ops — the gmap_walk_ops that will be used to perform the walk. these are the ones doing the actual strolling 🚶‍♀️
  • flags — flags from WALK_*, and rn literally only WALK_IGN_HOLES is supported (that's it, that's the whole list, she's a solo act 💀)
  • priv — gets passed as-is to the callbacks. no vibes check, no modifications, straight through 🌈

💖 DESCRIPTION 💖

here's the tea: any callback that returns non-zero causes the walk to stop immediately. like, instantly. walk's over, everyone go home 😭 so if your callback is out here returning nonzero for fun, that's on you fr fr

🔥 RETURN 🔥

  • -EINVAL — in case of error, classic 🫠
  • -EFAULT — if start is too high for the given ASCE, unless the DAT_WALK_IGN_HOLES flag is specified
  • otherwise — it returns whatever the callbacks return, literally whatever they hand back, that's the answer ✨
ngl bestie, peep that the flag list up in ARGUMENTS says WALK_IGN_HOLES and this RETURN bit says DAT_WALK_IGN_HOLES — both appear exactly like that in the original, so i'm keeping both spellings, no editing, no fixing, periodt 💅

🌸 SEE ALSO 🌸

kernel file ./arch/s390/kvm/gmap/dat.c, plus these iconic little friends:

go read them, they ate 👑

and that's the page!! 🎀 this little beauty comes from ./arch/s390/kvm/gmap and it's dated October 2026, filed under _dat_walk_gfn_range(9) — mwah, go walk some tables, ily, bye 🦋💜

📦 where this page comes from