bio_add_vmalloc_chunk(9)

📦 version 7.3.1, in nixpkgs unstable

💅 bio_add_vmalloc_chunk(9) — a Kernel API Manual moment

okay bestie, so this one lives in the Kernel API Manual and it's giving "small helper, big responsibility" energy. Let's get into it ✨

🎀 NAME 🎀

bio_add_vmalloc_chunk — literally just adds a vmalloc chunk to a bio. that's it. that's the whole job. 💖

✨ SYNOPSIS ✨

unsigned int bio_add_vmalloc_chunk (struct bio *bio , void *vaddr ,
       unsigned len );

like, three args, one unsigned int back. no cap, she's lowkey elegant 🦋

🌸 ARGUMENTS 🌸

  • bio — the destination bio. the ✨main character✨ of this whole operation, the one receiving the data 🫶
  • vaddr — the vmalloc address you're adding. yes, this specific one, pls don't mix it up 🙈
  • len — total length in bytes of the data you want to add. the full wishlist, basically 💅

💜 DESCRIPTION 💜

so what she does is: add the data starting at vaddr to bio, and then tell you how many bytes actually made it in. 🔥

heads up though — that number might be less than what you originally asked for. not a bug, just how she is. and if nothing at all could be added to bio, she returns 0. periodt 💀

she also calls flush_kernel_vmap_range for the range that got added — icon behavior, honestly, taking care of that for you 🧚

⚠️ but for reads? you're not off the hook, bestie. the caller still needs to manually call invalidate_kernel_vmap_range in the completion handler. don't forget, i'm begging 😭

🌈 SEE ALSO 🌈

fr fr, go read these too, they're all in the kernel file ./block/bio.c:

and that's the whole page, bestie 💖 this lil number came out of the ./block directory, dated October 2026, and she goes by bio_add_vmalloc_chunk(9) — go forth and slay your bio builds ✨👑

📦 where this page comes from