build_changeset(9)

Okay bestie, this is build_changeset(9) from the Kernel API Manual, and yes, we're doing kernel overlay changesets today. 💅✨

🌸 NAME 🌸

build_changeset is here to populate the overlay changeset in @ovcs from @ovcs->fragments. That's the assignment, no cap. 🫶

✨ SYNOPSIS ✨

int build_changeset (struct overlay_changeset *ovcs );

🎀 ARGUMENTS 🎀

• ovcs — Overlay changeset. It's the struct we're passing in, bestie; that's the whole argument. 💖

🦋 DESCRIPTION 🦋

Create changeset ovcs->cset so it contains the nodes and properties of the overlay device tree fragments in ovcs->fragments[]. Like, that's literally the mission. 📝

If an error occurs, any portions of the changeset that were successfully created will remain in ovcs->cset — no magical cleanup, they stay. 😭

🔥 RETURN 🔥

• 0 — success, slay. 👑
• -ENOMEM — memory allocation failure. 😭
• -EINVAL — invalid overlay in ovcs->fragments[]. 🚩

🌈 SEE ALSO 🌈

Go peek at these, iykyk:

• Kernel file ./drivers/of/overlay.c
• struct target(9)
• struct fragment(9)
• struct overlay_changeset(9)
• of_overlay_notifier_register(9)
• of_overlay_notifier_unregister(9)
• add_changeset_property(9)
• add_changeset_node(9)
• build_changeset_next_level(9)
• changeset_dup_entry_check(9)
• init_overlay_changeset(9)
• of_overlay_fdt_apply(9)
• of_overlay_remove(9)
• of_overlay_remove_all(9)

Final vibe check: this iconic page is from ./drivers/of, dated October 2026, and it's literally build_changeset(9). Periodt. 🫶💖