STRUCT IPC_PROTOCOL_AP_SHM(9)

💖 struct ipc_protocol_ap_shm — the kernel API manual bestie edition 💖

okay so listen 👑 this is the page for struct ipc_protocol_ap_shm, straight out of the Kernel API Manual — it's the Protocol Shared Memory Structure and honestly? it's kind of the main character of the shared-memory situation. let's get into it ✨

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🌸 NAME 🌸

struct ipc_protocol_ap_shm — Protocol Shared Memory Structure 💅 that's it, that's the whole name, no cap.

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✨ SYNOPSIS ✨

here's the whole struct, copy it exact because we do not freestyle kernel definitions 🫶

struct ipc_protocol_ap_shm {
    struct ipc_protocol_context_info ci;
    struct ipc_protocol_device_info device_info;
    __le32 msg_head;
    __le32 head_array[IPC_MEM_MAX_PIPES];
    __le32 msg_tail;
    __le32 tail_array[IPC_MEM_MAX_PIPES];
    union ipc_mem_msg_entry msg_ring[IPC_MEM_MSG_ENTRIES];
 };

look at her. gorgeous. iconic. the layout is immaculate 🌈

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🎀 Members 🎀

bestie these are the fields, do not lose track, we go in order ✨

• ci — the context information struct 🧚 literally the vibes/context of the whole thing
• device_info — the device information struct 💜 this is where the device spills its info
• msg_head — it points to the msg head, that's the whole job, lowkey dedicated
• head_array — an array of head pointers 🎯 like a little squad of heads
• msg_tail — points to the msg tail, the head's other half, cute
• tail_array — an array of tail pointers 🦋 a whole friend group of tails
• msg_ring — the circular buffers for the read/tail and write/head indeces 💀 (yes that's how it's spelled in the source, we don't edit, we report) — this is the actual ring where messages go round and round like a carousel 🎠

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🦋 SEE ALSO 🦋

okay the Kernel file is ./drivers/net/wwan/iosm/iosm_ipc_protocol.h and here's the whole friend group of structs and functions you should also go look at, all of them, no skipping 🙈

• struct ipc_protocol_context_info(9)
• struct ipc_protocol_device_info(9)
• struct iosm_protocol(9)
• struct ipc_call_msg_send_args(9)
• ipc_protocol_tq_msg_send(9)
• ipc_protocol_msg_send(9)
• ipc_protocol_suspend(9)
• ipc_protocol_s2idle_sleep(9)
• ipc_protocol_resume(9)
• ipc_protocol_pm_dev_sleep_handle(9)
• ipc_protocol_doorbell_trigger(9)
• ipc_protocol_sleep_notification_string(9)
• ipc_protocol_init(9)
• ipc_protocol_deinit(9)

like a whole group chat of related symbols fr fr 🔥 go say hi to all of them 💖

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okay that's the whole page, nothing left out, we ate and left zero crumbs 🍓💅

and that's a wrap bestie — shoutout to ./drivers/net/wwan/iosm for being the source directory, version October 2026 for the timestamp, and the title struct ipc_protocol_ap_shm(9) for the whole era 👑 see you in the next manpage, mwah 💜✨🎀