bio_copy_to_iter(9)

💅 bio_copy_to_iter(9) — like, the kernel API manual, bestie ✨

okay so real talk, this is from the Kernel API Manual and it's genuinely one of those little helper functions that does exactly what it says on the tin 🎀 no cap.

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🌸 NAME 🌸

bio_copy_to_iter — copy all the pages from a bio over to an iov_iter 💖 (yes, all of them, the whole thing, we're not doing half measures here)

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✨ SYNOPSIS ✨

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

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🫶 ARGUMENTS 🫶

• bio — the struct bio that describes the I/O, and it's serving as our source 💅 this is where the data lives
• iter — the iov_iter, and it's the destination 🎯 this is where everything's headed

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🦋 DESCRIPTION 🦋

so basically: copy all pages from bio to iov_iter ⭐ that's the whole vibe. it's giving "pack your bags, you're moving" and every single page is coming along 🌈

return value check, because we always check: it returns 0 on success 🎉 or an error on failure 😭 (so like, if you get something that isn't zero, that's your sign something went sideways — handle it, queen 👑)

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🔥 SEE ALSO 🔥

• Kernel file ./block/blk-map.c
• bio_copy_from_iter(9)
• bio_uncopy_user(9)
• bio_copy_kern(9)
• blk_rq_map_user_iov(9)
• blk_rq_unmap_user(9)
• blk_rq_map_kern(9)

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💀 reminder bestie: the description literally says "returns 0 on success, or error on failure" — that's the whole contract, don't go inventing extra behaviour, iykyk 🙈

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okay that's the whole page, mwah 💋 this one lives in ./block and it's dated October 2026 — so like, go forth and copy those pages, bestie, you're gonna slay 🧚💜