drain_slab(9)

💅 drain_slab(9) 💅

bestie, welcome to the Kernel API Manual page for drain_slab(9) — yes, that exact one, and we’re gonna get through it together. ✨

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🌸 NAME 🌸

drain_slab — Drain all reference count I/O.

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🎀 SYNOPSIS 🎀

void drain_slab (struct vdo_slab *slab );

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💖 ARGUMENTS 💖

• slab — The slab. That’s literally it, bestie: the slab. Minimal, iconic, no notes. 💅

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🦋 DESCRIPTION 🦋

okay so depending upon the type of drain being performed — and that type is recorded in the ref_count's vdo_slab — the reference blocks may be loaded from disk, or dirty reference blocks may be written out. no cap, that’s the whole vibe of this one. 🌈

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👑 SEE ALSO 👑

Kernel file: ./drivers/md/dm-vdo/slab-depot.c — yes, that’s the spot. Here’s the whole reference squad, in order, no skips:

• get_lock(9), must_make_entries_to_flush(9), is_reaping(9), initialize_tail_block(9), initialize_journal_state(9)
• block_is_full(9), is_slab_journal_blank(9), mark_slab_journal_dirty(9), compute_fullness_hint(9), check_summary_drain_complete(9)
• notify_summary_waiters(9), finish_updating_slab_summary_block(9), finish_update(9), handle_write_error(9), launch_write(9)
• update_slab_summary_entry(9), finish_reaping(9), complete_reaping(9), handle_flush_error(9), flush_for_reaping(9)
• reap_slab_journal(9), adjust_slab_journal_block_reference(9), release_journal_locks(9), update_tail_block_location(9), reopen_slab_journal(9)
• complete_write(9), write_slab_journal_block(9), commit_tail(9), encode_slab_journal_entry(9), expand_journal_point(9)
• add_entry(9), vdo_attempt_replay_into_slab(9), requires_reaping(9), launch_reference_block_write(9), finish_reference_block_write(9)
• get_reference_counters_for_block(9), pack_reference_block(9), handle_io_error(9), write_reference_block(9), reference_count_to_status(9)
• dirty_block(9), get_reference_block(9), slab_block_number_from_pbn(9), get_reference_counter(9), adjust_free_block_count(9)
• increment_for_data(9), decrement_for_data(9), increment_for_block_map(9), update_reference_count(9), add_entry_from_waiter(9)
• is_next_entry_a_block_map_increment(9), add_entries(9), reset_search_cursor(9), advance_search_cursor(9), vdo_adjust_reference_count_for_rebuild(9)
• replay_reference_count_change(9), find_zero_byte_in_word(9), find_free_block(9), search_current_reference_block(9), search_reference_blocks(9)
• make_provisional_reference(9), dirty_all_reference_blocks(9), match_bytes(9), count_valid_references(9), unpack_reference_block(9)
• finish_reference_block_load(9), load_reference_block_group(9), load_reference_blocks(9), read_slab_journal_tail(9), load_slab_journal(9)
• get_next_slab(9), has_slabs_to_scrub(9), uninitialize_scrubber_vio(9), finish_scrubbing(9), slab_scrubbed(9)
• abort_scrubbing(9), handle_scrubber_error(9), apply_block_entries(9), apply_journal_entries(9), start_scrubbing(9)
• scrub_next_slab(9), scrub_slabs(9), get_depot_slab_iterator(9), next_slab(9), abort_waiter(9)
• vdo_acquire_provisional_reference(9), open_slab(9), vdo_enqueue_clean_slab_waiter(9), vdo_modify_reference_count(9), vdo_notify_slab_journals_are_recovered(9)
• make_slab(9), allocate_slabs(9), vdo_abandon_new_slabs(9), release_recovery_journal_lock(9), prepare_for_tail_block_commit(9)
• schedule_tail_block_commit(9), initialize_slab_scrubber(9), initialize_slab_summary_block(9), vdo_decode_slab_depot(9), vdo_free_slab_depot(9)
• vdo_record_slab_depot(9), vdo_allocate_reference_counters(9), get_slab_number(9), vdo_get_slab(9), vdo_get_increment_limit(9)
• vdo_is_physical_data_block(9), vdo_get_slab_depot_allocated_blocks(9), vdo_get_slab_depot_data_blocks(9), finish_combining_zones(9), combine_summaries(9)
• finish_loading_summary(9), load_slab_summary(9), vdo_load_slab_depot(9), vdo_prepare_slab_depot_to_allocate(9), vdo_update_slab_depot_size(9)
• vdo_prepare_to_grow_slab_depot(9), finish_registration(9), vdo_use_new_slabs(9), stop_scrubbing(9), vdo_drain_slab_depot(9)
• resume_scrubbing(9), vdo_resume_slab_depot(9), vdo_commit_oldest_slab_journal_tail_blocks(9), vdo_scrub_all_unrecovered_slabs(9), get_block_allocator_statistics(9)
• get_ref_counts_statistics(9), get_slab_journal_statistics(9), vdo_get_slab_depot_statistics(9), vdo_dump_slab_depot(9)

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later, bestie — this page is from ./drivers/md/dm-vdo, dated October 2026, and it’s literally the drain_slab(9) manual page. 💖🫶