migrate_vma_split_folio(9)

migrate_vma_split_folio(9) from the Kernel API Manual — okay bestie, let's get into it 💖

🌸 NAME 🌸

migrate_vma_split_folio — the helper function that splits a THP folio. That's literally what it does, no cap 🫶

✨ SYNOPSIS ✨

int migrate_vma_split_folio (struct folio *folio , struct page
       *fault_page );

🎀 ARGUMENTS 🎀

• folio — the folio to split, bestie 🌸
• fault_page — the struct page associated with the fault if any 🦋

💅 DESCRIPTION 💅

okay so here's the tea: if folio is not the folio containing fault_page, then the caller must hold a reference on folio. The helper consumes that reference. Yes, it takes it — that's the whole vibe 😭

Returns 0 on success ✨

🦋 SEE ALSO 🦋

Kernel file ./mm/migrate_device.c — and the whole squad is:

• migrate_vma_setup(9)
• migrate_vma_insert_huge_pmd_page(9)
• migrate_device_pages(9)
• migrate_vma_pages(9)
• migrate_vma_finalize(9)
• migrate_device_range(9)
• migrate_device_pfns(9)

xoxo, source ./mm, dated October 2026 💜✨