STRUCT DOCG3(9)

✨ struct docg3 ✨

okay bestie, so this is the manual page for struct docg3 from the Kernel API Manual — it's literally the DiskOnChip driver's private data and it's giving backstage-pass energy 🎀 like this is where the driver keeps all its lil secrets.

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💖 NAME 💖

struct docg3 — the DiskOnChip driver's private data, no cap 💅

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🌸 SYNOPSIS 🌸

struct docg3 {
    struct device *dev;
    struct docg3_cascade *cascade;
    unsigned int device_id:4;
    unsigned int if_cfg:1;
    unsigned int reliable:2;
    int max_block;
    u8 *bbt;
    loff_t oob_write_ofs;
    int oob_autoecc;
    u8 oob_write_buf[DOC_LAYOUT_OOB_SIZE];
};

look at her. icon. the bitfields?? we love a memory-conscious queen 👑

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🦋 Members 🦋

so here's the full rundown of every single field, fr fr, and yes we're doing all of them because none of them are boring 💜

• dev — the device that's currently under control. main character of the moment ✨
• cascade — the cascade this device belongs to. iykyk, it's her family 🫶
• device_id — number of the cascaded DoCG3 device, and it's one of 0, 1, 2 or 3. that's it. that's the whole range 💅
• if_cfg — if true, reads are on 16bits; else reads are on 8bits. one bit deciding the whole read situation, lowkey powerful 🔥
• reliable — the mode check, and there are three whole moods:
  • 0 → docg3 in normal mode
  • 1 → docg3 in fast mode
  • 2 → reliable mode

bestie pls read this part: Fast mode implies more errors than normal mode. and Reliable mode implies that page 2*n and 2*n+1 are clones. not me warning you, just factually warning you 😭

• max_block — maximum block number for this device. the ceiling, literally 🧚
• bbt — bad block table cache. it remembers the bad ones so you don't have to 🙈
• oob_write_ofs — offset of the MTD where this OOB should belong (ie. in next page_write). keep that page_write exactly as written, periodt 🎀
• oob_autoecc — if 1, use only bytes 0-7, 15, and fill the others with HW ECC. if 0, use all the 16 bytes. so many bytes, so little time 🌸
• oob_write_buf — prepared OOB for next page_write. she's ready ahead of time, we stan a prepared queen 👑

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/mtd/devices/docg3.h
• struct docg3_cascade(9) — go read her too, she's iconic 💖

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ok that's the whole vibe check 💀 every field accounted for, nothing skipped, nothing invented. you're welcome 🫶

and finally, the cute lil sign-off: this page lives in ./drivers/mtd/devices, it's dated October 2026, and it's struct docg3(9) — go forth and slay your DiskOnChip driver era 👑⭐