iommufd_access_notify_unmap(9)

💅 iommufd_access_notify_unmap(9) 💅

okay bestie, welcome to the Kernel API Manual page for iommufd_access_notify_unmap(9) — this is the little notification that tells users of an iopt to stop using it, and honestly it’s giving “wrap it up” energy 🎀✨.

🦋 NAME 🦋

iommufd_access_notify_unmap — notify users of an iopt to stop using it. periodt 💅

✨ SYNOPSIS ✨

void iommufd_access_notify_unmap (struct io_pagetable *iopt , unsigned
long iova , unsigned long length );

🎀 ARGUMENTS 🎀

• iopt — the iopt to work on, aka the main character of this operation 👑.
• iova — starting iova in the iopt 🗺️.
• length — number of bytes 📏.

💖 DESCRIPTION 💖

okay so after this function returns, there should be no users attached to the pages linked to this iopt that intersect with iova,length — like, zero, none, nobody 💀. Anyone that has attached a user through iopt_access_pages needs to detach it through iommufd_access_unpin_pages before this function returns. no cap, that’s the whole vibe check 🙈.

iommufd_access_destroy will wait for any outstanding unmap callback to complete 🫶. After iommufd_access_destroy, no unmap ops are running or will run in the future.

⚠️ Due to this, a driver must not create locking that prevents unmap to complete while iommufd_access_destroy is running. That’s literally the caveat, don’t skip it 💅.

🌈 SEE ALSO 🌈

Kernel file: ./drivers/iommu/iommufd/device.c — yes, that’s the spot 🫶.

• iommufd_device_bind(9)
• iommufd_ctx_has_group(9)
• iommufd_device_unbind(9)
• iommufd_device_attach(9)
• iommufd_device_replace(9)
• iommufd_device_detach(9)
• iommufd_access_create(9)
• iommufd_access_destroy(9)
• iommufd_access_unpin_pages(9)
• iommufd_access_pin_pages(9)
• iommufd_access_rw(9)

xoxo, your kernel bestie — source ./drivers/iommu/iommufd, October 2026 🎀💖