bio_copy_from_iter(9)

💅 bio_copy_from_iter(9) 💅

okay so welcome to the Kernel API Manual, bestie. today’s main character is bio_copy_from_iter(9), and she is literally here to copy pages. no cap. ✨

🌸 NAME 🌸

bio_copy_from_iter — copy all pages from iov_iter to bio. that’s the whole vibe. 🎀

✨ SYNOPSIS ✨

int bio_copy_from_iter (struct bio *bio , struct iov_iter *iter );

🎀 ARGUMENTS 🎀

• bio — the struct bio that describes the I/O as destination. think: where the pages are headed, periodt. 💅
• iter — the iov_iter as source. think: where the pages are coming from, iykyk. 🦋

🦋 DESCRIPTION 🦋

Copy all pages from iov_iter to bio. that’s it, that’s the function. iconic behavior, honestly. 🔥

Returns 0 on success, or error on failure. so like, success is 0, failure is error — simple as that, bestie. 😭

🌈 SEE ALSO 🌈

the kernel file ./block/blk-map.c is the plug, and you should also check out bio_copy_to_iter(9), bio_uncopy_user(9), bio_copy_kern(9), blk_rq_map_user_iov(9), blk_rq_unmap_user(9), and blk_rq_map_kern(9). go read those next, fr fr. 👑🌸

okay bye bestie — this page is from ./block, dated October 2026, and it’s literally bio_copy_from_iter(9). 🫶✨