vdo_validate_config(9)

💖 vdo_validate_config(9) 💖

okay so this is a page from the Kernel API Manual (yes, the actual kernel API manual, we're fancy now 💅) and it's all about vdo_validate_config — which, as the name is literally giving, validates the constraints on a VDO config. bestie, it's a vibe check for your config 💖

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✨ NAME ✨

vdo_validate_config — validate constraints on a VDO config. that's it, that's the whole job 🫶

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🦋 SYNOPSIS 🦋

int vdo_validate_config (const struct vdo_config *config , block_count_t
physical_block_count , block_count_t logical_block_count );

look at her. three args, returns an int, no cap she's iconic 🔥

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🎀 ARGUMENTS 🎀

• config — the VDO config itself, the main character of this whole situation 👑
• physical_block_count — the minimum block count of the underlying storage. like the floor, the bare minimum, the "you must be at least this tall to ride" of storage 🎢
• logical_block_count — the expected logical size of the VDO... or 0 if the logical size may be unspecified. yeah she's optional-optional in that case, noted 📝

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⭐ RETURN ⭐

a success or error code. literally that's it — you get back a code, check it, move on, slay 💅

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🌈 SEE ALSO 🌈

okay this list is LONG, grab a snack 🍓 — all of these live in the kernel file ./drivers/md/dm-vdo/encodings.c:

• validate_version(9)
• vdo_validate_header(9)
• decode_volume_geometry(9)
• vdo_encode_volume_geometry(9)
• vdo_parse_geometry_block(9)
• vdo_compute_new_forest_pages(9)
• encode_recovery_journal_state_7_0(9)
• decode_recovery_journal_state_7_0(9)
• vdo_get_journal_operation_name(9)
• encode_slab_depot_state_2_0(9)
• decode_slab_depot_state_2_0(9)
• vdo_configure_slab_depot(9)
• vdo_configure_slab(9)
• vdo_decode_slab_journal_entry(9)
• allocate_partition(9)
• make_partition(9)
• vdo_initialize_layout(9)
• vdo_uninitialize_layout(9)
• vdo_get_partition(9)
• vdo_get_known_partition(9)
• pack_vdo_config(9)
• pack_vdo_component(9)
• unpack_vdo_config(9)
• unpack_vdo_component_41_0(9)
• decode_vdo_component(9)
• vdo_destroy_component_states(9)
• decode_components(9)
• vdo_decode_component_states(9)
• vdo_validate_component_states(9)
• vdo_encode_component_states(9)
• vdo_encode_super_block(9)
• vdo_decode_super_block(9)
• vdo_initialize_component_states(9)
• vdo_compute_index_blocks(9)
• vdo_initialize_volume_geometry(9)

like I said. long. but every single one of them is there, fr fr 💀✨

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lowkey reminder bestie: you pass in 0 for logical_block_count when the logical size is allowed to be unspecified — that's a real thing on this page, not me being cute 🌸

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okay that's the whole page!! this gem comes to you from ./drivers/md/dm-vdo, dated October 2026 — go forth and validate those configs, you're gonna eat 💖🎀🦋💜