STRUCT IOMMU_USER_DATA(9)

✨ NAME ✨

struct iommu_user_data — the iommu-driver-specific info about user space data, bestie 💅

So this is the little struct that carries around what an iommu driver needs to know about a chunk of user space data. Iconic, lowkey essential.

🌸 SYNOPSIS 🌸

struct iommu_user_data {
    unsigned int type;
    void __user *uptr;
    size_t len;
 };

🎀 Members 🎀

• type — the data type of the user buffer. Like, what is this data, actually? 👀
• uptr — pointer to the user buffer for copy_from_user. That's the address, bestie, handle with care 🫶
• len — the length of the user buffer in bytes. Gotta know how much we're working with fr fr 📏

💖 Description 💖

Okay so here's the vibe: a user space data is a uAPI that's defined in include/uapi/linux/iommufd.h — that's the blueprint, periodt. 📜

And the rule? type, uptr and len should be just copied from an iommufd core uAPI struct. No extra seasoning, no creative liberties, just copy them straight over. Slay, but like, literally copy them. 💀

🦋 SEE ALSO 🦋

• Kernel file ./include/linux/iommu.h ⭐
• struct iommu_fault_page_request(9)
• struct iommu_fault(9)
• enum iommu_page_response_code(9)
• struct iommu_page_response(9)
• struct iopf_queue(9)
• struct iommu_resv_region(9)
• struct iommu_iotlb_gather(9)
• struct iommu_dirty_bitmap(9)
• struct iommu_dirty_ops(9)
• struct iommu_user_data_array(9)
• __iommu_copy_struct_from_user(9)
• iommu_copy_struct_from_user(9)
• __iommu_copy_struct_from_user_array(9)
• iommu_copy_struct_from_user_array(9)
• iommu_copy_struct_from_full_user_array(9)
• __iommu_copy_struct_to_user(9)
• iommu_copy_struct_to_user(9)
• struct iommu_ops(9)
• struct iommu_domain_ops(9)
• struct iommu_device(9)
• struct iommu_fault_param(9)
• struct dev_iommu(9)
• iommu_iotlb_gather_is_disjoint(9)
• iommu_iotlb_gather_add_range(9)
• iommu_iotlb_gather_add_page(9)
• struct iommu_fwspec(9)
• struct iommu_sva(9)
• iommu_map_sgtable(9)

And that's the whole page, bestie! 🫶 This one lives in ./include/linux, dated October 2026, from the Kernel API Manual — struct iommu_user_data(9). Go off, read the source, ily. 💖✨