gfs2_next_unreserved_block(9)

💅 gfs2_next_unreserved_block — Kernel API Manual, section 9 🦋

okay so bestie, we're in the kernel API manual (section 9, the fun one) and today's main character is gfs2_next_unreserved_block ✨

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🌸 NAME 🌸

gfs2_next_unreserved_block — returns the next block that is not reserved, no cap 💅

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✨ SYNOPSIS ✨

u64 gfs2_next_unreserved_block (struct gfs2_rgrpd *rgd , u64 block , u32
length , struct gfs2_blkreserv *ignore_rs );

literally just copy that signature exactly, don't be weird about it 🫶

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🎀 ARGUMENTS 🎀

• rgd — the resource group. yes. that one. 👑
• block — the starting block, aka where we begin the hunt 🕵️‍♀️
• length — the required length. we need this much, fr fr 🍓
• ignore_rs — the reservation to ignore 🙈 like we're pretending it's not even there

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💖 DESCRIPTION 💖

so here's the vibe check 🔥 if the block does not appear in any reservation, then we return the block number unchanged — no notes, no edits, she stays exactly as she came in 💅

but if it does appear in the reservation? that's when we go looking 👀 we keep looking through the tree of reservations in order to find the first block number which is not reserved. that's the whole gig. that's the mission. slay 🌈

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🧚 SEE ALSO 🧚

kernel file ./fs/gfs2/rgrp.c — and the entire group chat of friends, all present and accounted for, nobody left on read:

• gfs2_setbit(9), gfs2_testbit(9), gfs2_bit_search(9), rs_cmp(9), gfs2_bitfit(9), gfs2_rbm_from_block(9), gfs2_rbm_add(9), gfs2_unaligned_extlen(9), gfs2_free_extlen(9), gfs2_bitcount(9), gfs2_rgrp_verify(9), gfs2_blk2rgrpd(9), gfs2_rgrpd_get_first(9), gfs2_rgrpd_get_next(9), __rs_deltree(9), gfs2_rs_deltree(9), gfs2_rs_delete(9), return_all_reservations(9), compute_bitstructs(9), gfs2_ri_total(9), read_rindex_entry(9), set_rgrp_preferences(9), gfs2_ri_update(9), gfs2_rindex_update(9), gfs2_rgrp_go_instantiate(9), gfs2_rgrp_brelse(9), gfs2_fitrim(9), rs_insert(9), rgd_free(9), rg_mblk_search(9), gfs2_reservation_check_and_update(9), gfs2_rbm_find(9), try_rgrp_unlink(9), gfs2_rgrp_congested(9), gfs2_rgrp_used_recently(9), fast_to_acquire(9), gfs2_inplace_reserve(9), gfs2_inplace_release(9), gfs2_alloc_extent(9), rgblk_free(9), gfs2_rgrp_dump(9), gfs2_adjust_reservation(9), gfs2_set_alloc_start(9), gfs2_alloc_blocks(9), __gfs2_free_blocks(9), gfs2_free_meta(9), gfs2_check_blk_type(9), gfs2_rlist_add(9), gfs2_rlist_alloc(9), gfs2_rlist_free(9)

like… fifty of them?? and every single one made the list. iconic behavior honestly 💀👑

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lowkey reminder bestie: this page is living in ./fs/gfs2 and it's stamped October 2026 — that's the source folder and the date, keep them safe 🫶

and that's the page!! mwah 💋 — signed off from the Kernel API Manual, gfs2_next_unreserved_block(9), dated October 2026, source ./fs/gfs2. periodt. 🌟