dma_iova_free(9)

📦 version 7.3.1, in nixpkgs unstable

💖 dma_iova_free(9) — like, the kernel API manual, but make it make sense 🎀

okay bestie, welcome to dma_iova_free from the 9 section of the Kernel API Manual — yes we're in kernel-land, yes it's giving big-brain energy, and yes I'm gonna walk you through it like we're texting at 2am 💅

✨ NAME ✨

dma_iova_free — Free an IOVA space 🦋

like literally, it's the "ok we're done here, release the space" function, no cap

🌸 SYNOPSIS 🌸

void dma_iova_free (struct device *dev , struct dma_iova_state *state );

that's it. that's the whole signature. returns void, so nothing to catch, nothing to check — she just does her thing and leaves ✨

🎀 ARGUMENTS 🎀

  • dev — the device you're freeing the IOVA space for 🫶 like, which device's space are we cleaning up, bestie
  • state — the IOVA state 💜 the actual state struct that's holding the IOVA info

🔥 DESCRIPTION 🔥

So here's the tea ☕ this function undoes a successful dma_try_iova_alloc. That's the whole vibe. You allocated, now you're freeing. Balance restored, universe aligned, slay 🌈

⚠️ but like, read this part twice, bestie: all dma_iova_link calls need to be undone first. Every single one. No skipping. The function will not do it for you and I'm not gonna pretend it will 💀

And for the girlies who never call dma_iova_unlink — good news 🎉 there's dma_iova_destroy instead, which unlinks all ranges and frees the IOVA space in a single efficient operation. one call, everything handled, main character energy 👑

so like:

  • linked stuff? → undo it first, then dma_iova_free
  • never linked anything / never unlink? → just use dma_iova_destroy and move on 🧚

💫 SEE ALSO 💫

Kernel file ./drivers/iommu/dma-iommu.c — that's where the magic lives, iykyk 📁✨

and the whole friend group:

lowkey the funniest part is the description says dma_try_iova_alloc and SEE ALSO says dma_iova_try_alloc(9) — I'm not touching it, I'm just reporting what the page says 🙈 keep both, they're both here, we don't edit manpages in this house

and that's the page, bestie 🍓 straight from ./drivers/iommu, dated October 2026, filed under dma_iova_free(9) — go forth responsibly, unlink before you free, and stan efficient cleanup 💖✨

📦 where this page comes from