gfs2_adjust_reservation(9)

💅 NAME 💅

okay so welcome to the Kernel API Manual, bestie — this page is gfs2_adjust_reservation(9), and it does exactly one job: it adjusts (or honestly just removes) a reservation after an allocation. that's the whole vibe. 🎀

✨ SYNOPSIS ✨

void gfs2_adjust_reservation (struct gfs2_inode *ip , const struct gfs2_rbm *rbm , unsigned len );

like, literally copy it exactly, no cap 💅

🎀 ARGUMENTS 🎀

• ip — the inode we have just allocated blocks for. yeah. the whole reason we're here. main character energy fr.
• rbm — the start of the allocated blocks. it's giving "beginning of the block situation" ✨
• len — the extent length. how long the extent is. that's it, that's the girl 🦋

🦋 DESCRIPTION 🦋

so picture this: an allocation already happened, and now the reservation needs its little post-allocation glow-up. that's what this does — it adjusts a reservation after an allocation has taken place.

and here's the ✨plot twist✨: if the reservation does not match the allocation, or if it is now empty, then it is removed. gone. deleted. not me ghosting a stale reservation 😭

lowkey important: both of those conditions mean the reservation gets removed — mismatch or empty. don't forget the second one, bestie.

🌈 SEE ALSO 🌈

the kernel file is ./fs/gfs2/rgrp.c — that's where all this lives, iykyk 🫶

and because the kernel devs were feeling generous, here's the whole friend group (keep them in order, they're iconic):

• 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_next_unreserved_block(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_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)

and that's the page!! 🫶 sourced straight from ./fs/gfs2, stamped October 2026 — catch you in the next (9) bestie, mwah 💖🌸