STRUCT UBI_DEBUG_INFO(9)

💅 struct ubi_debug_info(9) 🌸

okay bestie, welcome to the Kernel API Manual — this one's a whole vibe, trust. It's all about struct ubi_debug_info, which is literally the debugging information holder for an UBI device. Yes, the name is doing the heavy lifting and honestly? Slay. 🎀

✨ SYNOPSIS ✨

here's the whole squad, laid out exactly as they appear, no cap:

struct ubi_debug_info {
    unsigned int chk_gen:1;
    unsigned int chk_io:1;
    unsigned int chk_fastmap:1;
    unsigned int disable_bgt:1;
    unsigned int emulate_bitflips:1;
    unsigned int emulate_io_failures:1;
    unsigned int emulate_power_cut:2;
    unsigned int power_cut_counter;
    unsigned int power_cut_min;
    unsigned int power_cut_max;
    unsigned int emulate_failures;
    char dfs_dir_name[UBI_DFS_DIR_LEN];
    struct dentry *dfs_dir;
    struct dentry *dfs_chk_gen;
    struct dentry *dfs_chk_io;
    struct dentry *dfs_chk_fastmap;
    struct dentry *dfs_disable_bgt;
    struct dentry *dfs_emulate_bitflips;
    struct dentry *dfs_emulate_io_failures;
    struct dentry *dfs_emulate_power_cut;
    struct dentry *dfs_power_cut_min;
    struct dentry *dfs_power_cut_max;
    struct dentry *dfs_emulate_failures;
 };

🌈 Members 🌈

okay so this is the part where we meet everybody individually. main character energy for each field, honestly 👑

• chk_gen — if UBI general extra checks are enabled 💖
• chk_io — if UBI I/O extra checks are enabled ✨
• chk_fastmap — if UBI fastmap extra checks are enabled 🦋
• disable_bgt — disables the background task, purely for testing purposes 🙈
• emulate_bitflips — emulates bit-flips, for testing purposes 💀
• emulate_io_failures — emulates write/erase failures, for testing purposes 😭
• emulate_power_cut — emulates power cuts, for testing purposes 🔥
• power_cut_counter — the countdown for writes left until the emulated power cut hits ⏳
• power_cut_min — the minimum number of writes before emulating a power cut 🌸
• power_cut_max — the maximum number of writes until emulating a power cut 🎀
• emulate_failures — emulates failures, for testing purposes 🫶
• dfs_dir_name — the name of the debugfs directory that contains the files of this UBI device 📁
• dfs_dir — the direntry object of the UBI device debugfs directory 🗂️
• dfs_chk_gen — debugfs knob to enable UBI general extra checks ⭐
• dfs_chk_io — debugfs knob to enable UBI I/O extra checks ⭐
• dfs_chk_fastmap — debugfs knob to enable UBI fastmap extra checks ⭐
• dfs_disable_bgt — debugfs knob to disable the background task 💅
• dfs_emulate_bitflips — debugfs knob to emulate bit-flips 💅
• dfs_emulate_io_failures — debugfs knob to emulate write/erase failures 💅
• dfs_emulate_power_cut — debugfs knob to emulate power cuts 💅
• dfs_power_cut_min — debugfs knob for minimum writes before power cut 💅
• dfs_power_cut_max — debugfs knob for maximum writes until power cut 💅
• dfs_emulate_failures — debugfs entry to control the fault injection type 🧚

ngl bestie, a lot of these say "for testing purposes" — that's not me being cute, that's literally the deal. These knobs are for testing, so don't go treating them like normal everyday settings, mwah 💜

👀 SEE ALSO 👀

the whole extended fam — go say hi:

the kernel file ./drivers/mtd/ubi/ubi.h, plus struct ubi_vid_io_buf(9), struct ubi_wl_entry(9), struct ubi_ltree_entry(9), struct ubi_rename_entry(9), struct ubi_fastmap_layout(9), struct ubi_fm_pool(9), struct ubi_eba_leb_desc(9), struct ubi_volume(9), struct ubi_volume_desc(9), struct ubi_device(9), struct ubi_ainf_peb(9), struct ubi_ainf_volume(9), struct ubi_attach_info(9), struct ubi_work(9), ubi_init_vid_buf(9), ubi_free_vid_buf(9), ubi_get_vid_hdr(9), ubi_ro_mode(9), vol_id2idx(9), idx2vol_id(9), ubi_is_fm_vol(9), ubi_find_fm_block(9)

and that's the page, bestie!! 🫶 this lil masterpiece lives at ./drivers/mtd/ubi, stamped October 2026, and it's filed under struct ubi_debug_info(9) — go forth and debug iconic-ly 💖✨🌷