STRUCT ETHOC(9)

💖 struct ethoc(9) — the driver's lil private clubhouse 🏠✨

okay so bestie, picture this: you're deep in the kernel, you're writing a network driver, and you need somewhere to keep All Your Stuff. That's this struct. It's the driver-private device structure for the ethoc driver, and it is literally the main character of ./drivers/net/ethernet/ethoc.c. No cap. 🫶

This page lives in the Kernel API Manual, section 9 — the one for kernel internals, iykyk. 🌈

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✨ SYNOPSIS ✨

struct ethoc {
    void __iomem *iobase;
    void __iomem *membase;
    bool big_endian;
    unsigned int num_bd;
    unsigned int num_tx;
    unsigned int cur_tx;
    unsigned int dty_tx;
    unsigned int num_rx;
    unsigned int cur_rx;
    void **vma;
    struct net_device *netdev;
    struct napi_struct napi;
    u32 msg_enable;
    spinlock_t lock;
    struct mii_bus *mdio;
    struct clk *clk;
    s8 phy_id;
    int old_link;
    int old_duplex;
 };

like, look at her. every field accounted for, nothing extra, so organized. we stan a tidy struct. 🎀

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🌸 Members 🌸

okay now the meet-the-cast portion of the page, let's go member by member 💅

• iobase — pointer to the I/O memory region. her home base 🏡
• membase — pointer to the buffer memory region. the other home base, but for buffers 🧚
• big_endian — just big or little (endian). that's it, that's the whole vibe check 🔄
• num_bd — number of buffer descriptors 📋
• num_tx — number of send buffers 📤
• cur_tx — last send buffer written ✍️
• dty_tx — last buffer actually sent. past tense, bestie, it's gone 🚀
• num_rx — number of receive buffers 📥
• cur_rx — current receive buffer 👀
• vma — pointer to array of virtual memory addresses for buffers 🗺️
• netdev — pointer to network device structure. the whole reason we're here ngl 🌐
• napi — NAPI structure ⚡
• msg_enable — device state flags 🚩
• lock — device lock 🔒
• mdio — MDIO bus for PHY access 🔌
• clk — clock ⏰
• phy_id — address of attached PHY 🪪
• old_link — previous link info 🔗
• old_duplex — previous duplex info 🔁

bestie note: nothing here is optional reading, these are all just fields of one struct, so don't come for me about the bullet list. every single one is listed, periodt. 💀

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👑 SEE ALSO 👑

if you want the lore extended universe, go read the kernel file ./drivers/net/ethernet/ethoc.c, plus these absolute icons:

• struct ethoc_bd(9)
• ethoc_probe(9)
• ethoc_remove(9)

like, the whole squad. read them fr fr 📚🦋

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and that's the page!! sourced from way down in ./drivers/net/ethernet, dated October 2026, section 9 of the Kernel API Manual — ty for coming to my ted talk, ily, go read the other ethoc pages 🫶💖🌸✨🍓