is_idx_node_in_use(9)

💅 is_idx_node_in_use(9) — or, "girl, is this index node even still valid?"

ok so real talk, this is a page from the Kernel API Manual and it's about UBIFS internals, but don't panic bestie, we're gonna get through it together 🫶

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✨ NAME ✨

is_idx_node_in_use — literally just figuring out whether an index node can be overwritten or not. that's the whole vibe check 💅

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🌸 SYNOPSIS 🌸

int is_idx_node_in_use (struct ubifs_info *c , union ubifs_key *key ,
int level , int lnum , int offs );

yes the spacing is weird, no we're not fixing it, it's iconic as-is ✨

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🎀 ARGUMENTS 🎀

• c — the UBIFS file-system description object. your main character struct, fr fr 👑
• key — the key of the index node. its little ID tag 🏷️
• level — the index node level. where it sits in the hierarchy, iykyk
• lnum — the LEB number of the index node. which LEB it lives in 📍
• offs — the offset of the index node. exactly where inside that LEB, no cap

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🦋 DESCRIPTION 🦋

okay so here's the tea ☕

if key / lnum / offs identify an index node that was not part of the old index, then this function returns 0 (obsolete). like, it's not in the group chat anymore, it's done 💀

else, if the index node was part of the old index but is now dirty, 1 is returned. messy but still around, we respect it 🙈

else, if it is clean, 2 is returned. pristine, glowed up, no notes ✨

and if something goes wrong? a negative error code is returned on failure. 😭 not the error code era

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👑 SEE ALSO 👑

genuinely obsessed with how long this list is, she's a connector, a social butterfly, a main character 🧚

Kernel file ./fs/ubifs/tnc_commit.c, plus:

make_idx_node(9), fill_gap(9), find_old_idx(9), layout_leb_in_gaps(9), get_leb_cnt(9), layout_in_gaps(9), layout_in_empty_space(9), layout_commit(9), find_first_dirty(9), find_next_dirty(9), get_znodes_to_commit(9), alloc_idx_lebs(9), free_unused_idx_lebs(9), free_idx_lebs(9), ubifs_tnc_start_commit(9), write_index(9), free_obsolete_znodes(9), return_gap_lebs(9), ubifs_tnc_end_commit(9)

like ok go off, read the whole squad 💜

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and that's the page babes 🍓 this one comes from ./fs/ubifs, dated October 2026, filed under is_idx_node_in_use(9) — mwah, slay, periodt 💖🔥