iommu_put_msi_cookie(9)

💖 iommu_put_msi_cookie — a Kernel API Manual moment 💖

okay so bestie, welcome to the Kernel API Manual ✨ this one's short and sweet and it's literally about cleaning up after yourself, which is so main character of you.

---

🌸 NAME 🌸

iommu_put_msi_cookie — release a domain's MSI mapping resources 🎀

like, you grabbed the cookie earlier, now put it back. that's it. that's the vibe check. 💅

---

✨ SYNOPSIS ✨

void iommu_put_msi_cookie (struct iommu_domain *domain );

no return value, ngl — it's a void function, it just does the thing and leaves. iconique. 🦋

---

🫶 ARGUMENTS 🫶

• domain — the IOMMU domain that you previously prepped with iommu_get_msi_cookie. yes, the same one. the one you already had. don't come in here with a random domain, bestie, that's not the assignment 😭

---

🔥 SEE ALSO 🔥

the whole friend group, fr fr — this all lives in the kernel file ./drivers/iommu/dma-iommu.c:

• iommu_get_dma_cookie(9)
• iommu_get_msi_cookie(9)
• iommu_put_dma_cookie(9)
• iommu_dma_get_resv_regions(9)
• iommu_dma_init_options(9)
• iommu_dma_init_domain(9)
• dma_info_to_prot(9)
• dma_iova_try_alloc(9)
• dma_iova_free(9)
• dma_iova_link(9)
• dma_iova_sync(9)
• dma_iova_unlink(9)
• dma_iova_destroy(9)

go read them, iykyk 👑

---

ngl the get/put symmetry here is giving "you made the mess, you clean it up" and honestly? we respect it. pair this with iommu_get_msi_cookie or it's lowkey just you releasing something you never grabbed 🙈

---

and that's the whole page, bestie, you ate that 💜 this lil slice of the Kernel API Manual came from ./drivers/iommu and it's dated October 2026 — so go forth, release those MSI mapping resources, and slay 🌈💖🎀