STRUCT TEE_IOCTL_SHM_REGISTER_FD_DATA(9)

🎀 struct tee_ioctl_shm_register_fd_data(9) 🎀

okay so bestie, you found a page from the Kernel API Manual — yes, that one, the big scary one 💅 — and honestly? This one's a lil cutie. It's a struct. It's about shared memory registration. Let's get into it ✨

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🌸 NAME 🌸

struct tee_ioctl_shm_register_fd_data — the shared memory registering argument 🫶

Like, it's literally the argument struct. That's its whole job. And it slays at it.

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✨ SYNOPSIS ✨

struct tee_ioctl_shm_register_fd_data {
    __s64 fd;
    __u64 size;
    __u32 flags;
    __s32 id;
 };

Look at her. Four fields. Perfectly balanced. Not me being obsessed with a C struct 😭

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💖 Members 💖

• fd — [in] bestie this is the file descriptor that identifies the dmabuf reference 👑 you hand it in, it's your ticket
• size — [out] the size of the referenced memory, coming back at you 💫
• flags — [in] the flags going to/from allocation, okurrr 🦋
• id — [out] the identifier of the shared memory, and there she is ⭐

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🧚 Description 🧚

So here's the vibe check: the flags field should currently be zero as input 🚨 — like, zero, nada, nothing, keep it empty bestie. It then gets updated by the call with the actual flags, as defined by TEE_IOCTL_SHM_* above 🌈 (iykyk, scroll up, they're right there).

This structure is used as the argument for TEE_IOC_SHM_REGISTER_FD below 👇 and that's literally the whole dynamic.

ngl, "should currently be zero as input" is the kind of note you do NOT want to gloss over 🙈 keep that field at zero on your way in, fr fr.

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🔥 SEE ALSO 🔥

okay so this is the extended universe, get comfy:

• Kernel file ./include/uapi/linux/tee.h 📁
• struct tee_ioctl_version_data(9)
• TEE_IOC_VERSION(9)
• struct tee_ioctl_shm_alloc_data(9)
• TEE_IOC_SHM_ALLOC(9)
• struct tee_ioctl_buf_data(9)
• struct tee_ioctl_param(9)
• struct tee_ioctl_open_session_arg(9)
• TEE_IOC_OPEN_SESSION(9)
• struct tee_ioctl_invoke_arg(9)
• TEE_IOC_INVOKE(9)
• struct tee_ioctl_cancel_arg(9)
• TEE_IOC_CANCEL(9)
• struct tee_ioctl_close_session_arg(9)
• TEE_IOC_CLOSE_SESSION(9)
• struct tee_iocl_supp_recv_arg(9)
• TEE_IOC_SUPPL_RECV(9)
• struct tee_iocl_supp_send_arg(9)
• TEE_IOC_SUPPL_SEND(9)
• struct tee_ioctl_shm_register_data(9)
• TEE_IOC_SHM_REGISTER_FD(9)
• TEE_IOC_SHM_REGISTER(9)
• struct tee_ioctl_object_invoke_arg(9)

That's the whole friend group 💜 go read them too, they're iconic.

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✨ and that's the page! sign-off time: this lil gem lives in ./include/uapi/linux 📂 and it's dated October 2026 🗓️ — go off, bestie, struct your heart out 💅🎀💖