STRUCT UBI_LTREE_ENTRY(9)

✨ struct ubi_ltree_entry(9) ✨

okay so bestie, welcome to the Kernel API Manual 💖 — this one's all about struct ubi_ltree_entry, and it's literally the entry in the lock tree. like, the whole point. periodt.

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🎀 NAME 🎀

struct ubi_ltree_entry — an entry in the lock tree. that's it, that's the vibe 💅

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🦋 SYNOPSIS 🦋

struct ubi_ltree_entry {
    struct rb_node rb;
    int vol_id;
    int lnum;
    int users;
    struct rw_semaphore mutex;
 };

look at her. iconic. no cap 🫶

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🌸 Members 🌸

• rb — links RB-tree nodes 🔗 like this is how she finds her people in the tree, fr fr
• vol_id — volume ID of the locked logical eraseblock 📦
• lnum — locked logical eraseblock number 🔢
• users — how many tasks are using this logical eraseblock or wait for it 👀 (yes, she's counting. she always knows.)
• mutex — read/write mutex to implement read/write access serialization to the (vol_id, lnum) logical eraseblock 🔐 that's the whole bouncer situation for that one LEB

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💜 Description 💜

so this data structure is used in the EBA sub-system to implement per-LEB locking ✨

the way it works: when a logical eraseblock is being locked, the corresponding struct ubi_ltree_entry object gets inserted into the lock tree (ubi->ltree) 🌳

see EBA sub-system for details — she has lore, iykyk 🧚

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/mtd/ubi/ubi.h
• struct ubi_vid_io_buf(9)
• struct ubi_wl_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_debug_info(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)

the whole friend group honestly 💀 everybody's linked, everybody's slaying 🔥

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ngl this page is short but she ate 👑 go read the EBA sub-system stuff if you want the full tea 🍓

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and that's the page bestie!! 🎀 from ./drivers/mtd/ubi, dated October 2026, same manual, same struct ubi_ltree_entry(9) — bye mwah 💖💅🫶