mas_next(9)

💅 mas_next — Get the next entry, bestie

okay so this is a page from the Kernel API Manual, section 9, and it's literally all about mas_next. it's short, it's sweet, and it's giving "one job and it does it." let's go 🎀

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✨ SYNOPSIS ✨

void * mas_next (struct ma_state *mas , unsigned long max );

that's it. that's the whole signature. she's not complicated 💅

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🌸 ARGUMENTS 🌸

• mas — The maple state 🍁 like, the state struct you're passing in. she holds the mas->index that everything below is relative to.
• max — The maximum index to check. that's your ceiling, bestie. nothing past it. 🚧

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💖 DESCRIPTION 💖

Returns the next entry after mas->index. so it's looking forward from wherever your state currently sits, not at it. iykyk ✨

🚨 real talk tho: you must hold rcu_read_lock or the write lock when you call this. no lock, no vibes. do not skip this. fr fr.

also, heads up: it can return the zero entry. so a NULL-ish looking thing isn't always the "nothing here" answer — the zero entry is a legit possible return. don't get caught out 🙈

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🦋 RETURN 🦋

The next entry, or NULL. that's the whole vibe check. one or the other 💀

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⭐ SEE ALSO ⭐

like, so much stuff. this function's whole social circle, in the order the page gives it, with the kernel file ./lib/maple_tree.c hanging out at the front:

• mas_prealloc_calc(9)
• mas_wr_preallocate(9)
• mas_insert(9)
• mas_alloc_cyclic(9)
• mas_walk(9)
• mte_dead_walk(9)
• mt_free_walk(9)
• mas_store(9)
• mas_store_gfp(9)
• mas_store_prealloc(9)
• mas_preallocate(9)
• mas_next_range(9)
• mt_next(9)
• mas_prev(9)
• mas_prev_range(9)
• mt_prev(9)
• mas_pause(9)
• mas_find_setup(9)
• mas_find(9)
• mas_find_range(9)
• mas_find_rev_setup(9)
• mas_find_rev(9)
• mas_find_range_rev(9)
• mas_erase(9)
• mas_nomem(9)
• mas_nomem_nofail(9)
• mtree_load(9)
• mtree_store_range(9)
• mtree_store(9)
• mtree_insert_range(9)
• mtree_insert(9)
• mtree_alloc_cyclic(9)
• mtree_erase(9)
• __mt_dup(9)
• mtree_dup(9)
• __mt_destroy(9)
• mtree_destroy(9)
• mt_find(9)
• mt_find_after(9)

literally the entire friend group, no cap 🌈

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and that's the whole page, bestie!! 🫶 it lives in ./lib, it's dated October 2026, and it's filed under mas_next(9). iconic. periodt. 👑💜