netfs_readahead(9)

🌸 NAME 🌸

netfs_readahead — Helper to manage a read request

Okay bestie, this is netfs_readahead(9) from the Kernel API Manual, and we're about to make readahead make sense. ✨

🦋 SYNOPSIS 🦋

void netfs_readahead (struct readahead_control *ractl );

🎀 ARGUMENTS 🎀

• ractl — the description of the readahead request. That's the whole request-info package, bestie. 🫶

💅 DESCRIPTION 💅

Okay so netfs_readahead is the helper that fulfils a readahead request. It draws data from the cache if possible, or from the netfs if not. Iconic behaviour, no cap. 💖

Space beyond the EOF is zero-filled. Literally filled with zeroes. ✨

Multiple I/O requests from different sources will get munged together. Yes, munged — it's giving chaotic but functional, and that's the vibe. 😭

If necessary, the readahead window can be expanded in either direction to a more convenient alignment for RPC efficiency or to make storage in the cache feasible. Slay for efficiency. 🔥

The calling netfs must initialise a netfs context contiguous to the vfs inode before calling this. Like, non-negotiable, bestie — do that first. 💅

This is usable whether or not caching is enabled. Periodt. 👑

👑 SEE ALSO 👑

• Kernel file ./fs/netfs/buffered_read.c — plus netfs_read_folio(9), netfs_write_begin(9), netfs_buffered_read_iter(9), and netfs_file_read_iter(9). Iykyk, go read those too. 🦋

Mwah 💋 — source ./fs/netfs, dated October 2026, page netfs_readahead(9). That's the footer, bestie. Bye! 🫶✨