vdo_allow_re...y_mode_entry(9)

💅 vdo_allow_read_only_mode_entry(9) — like, the whole manual page, bestie ✨

okay so real talk, this is a page straight outta the Kernel API Manual, and the function is vdo_allow_read_only_mode_entry. yes the title up top is truncated as vdo_allow_re...y_mode_entry(9) because apparently even kernel docs get the ellipsis treatment 😭 but we're spelling the whole thing out here. let's GO 🎀

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✨ NAME ✨

vdo_allow_read_only_mode_entry — this one lets the notifier actually put the VDO into read-only mode, which is basically the undo button for vdo_wait_until_not_entering_read_only_mode(). it's giving "you may now proceed" energy 🫶

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🌸 SYNOPSIS 🌸

void vdo_allow_read_only_mode_entry (struct vdo_completion *parent );

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🦋 ARGUMENTS 🦋

• parent — the object we're gonna notify once the whole thing is done. like the designated bestie who gets the text when it's over 💌

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🔥 DESCRIPTION 🔥

so picture this: some thread tried to put the vdo into read-only mode while notifications were disallowed. rude, honestly. but not to worry — that whole thing gets done when this method is called. the way that works is: if that happens, the parent does not get notified until the vdo has actually entered read-only mode AND attempted to save the super block. no cap, no shortcuts, the notification waits its turn. 👑

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🧚 CONTEXT 🧚

okay this part is important, do not skip it —

this method may only be called from the admin thread. like, that's the rule. periodt. 💅

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🌈 SEE ALSO 🌈

the full squad, in the order they showed up, no one left out 💖 Kernel file ./drivers/md/dm-vdo/vdo.c Introduction(9), vdo_initialize_device_registry_once(9), filter_vdos_locked(9), vdo_find_matching(9), initialize_thread_config(9), get_thread_name(9), vdo_make_thread(9), register_vdo(9), vdo_format(9), initialize_vdo(9), vdo_make(9), free_listeners(9), unregister_vdo(9), vdo_destroy(9), finish_reading_super_block(9), handle_super_block_read_error(9), vdo_load_super_block(9), vdo_get_backing_device(9), vdo_get_device_name(9), vdo_synchronous_flush(9), vdo_get_state(9), vdo_set_state(9), vdo_get_admin_state(9), record_vdo(9), continue_parent(9), handle_geometry_block_save_error(9), vdo_save_geometry_block(9), handle_super_block_save_error(9), vdo_save_super_block(9), vdo_save_components(9), vdo_register_read_only_listener(9), notify_vdo_of_read_only_mode(9), vdo_enable_read_only_entry(9), vdo_wait_until_not_entering_read_only_mode(9), as_notifier(9), finish_entering_read_only_mode(9), make_thread_read_only(9), vdo_enter_read_only_mode(9), vdo_is_read_only(9), vdo_in_read_only_mode(9), vdo_in_recovery_mode(9), vdo_enter_recovery_mode(9), complete_synchronous_action(9), perform_synchronous_action(9), set_compression_callback(9), vdo_set_compressing(9), vdo_get_compressing(9), vdo_get_physical_blocks_allocated(9), vdo_get_physical_blocks_overhead(9), get_vdo_statistics(9), vdo_fetch_statistics_callback(9), vdo_fetch_statistics(9), vdo_get_callback_thread_id(9), vdo_dump_status(9), vdo_assert_on_admin_thread(9), vdo_assert_on_logical_zone_thread(9), vdo_assert_on_physical_zone_thread(9), vdo_get_physical_zone(9)

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and that's the page!! tysm for reading, ily, go call this from the admin thread and nowhere else 🌟

this masterpiece lives in ./drivers/md/dm-vdo and it's stamped October 2026 — mwah, xoxo, the kernel docs committee 💋