__smb2_copychunk_range(9)

okay so bestie, welcome to the Kernel API Manual page for __smb2_copychunk_range(9) — we're doing a server-side copy of a data range and it's lowkey iconic. 💖

🌸 NAME 🌸

__smb2_copychunk_range — server-side copy of data range ✨

🦋 SYNOPSIS 🦋

int __smb2_copychunk_range (const unsigned int xid , struct cifsFileInfo
*src_file , struct cifsFileInfo *dst_file , u64 src_off , u64 len , u64
dst_off );

🎀 ARGUMENTS 🎀

• xid — transaction id, the little receipt for the whole operation 🧾
• src_file — source file, aka where the data is coming from 👑
• dst_file — destination file, aka where the data is going 🫶
• src_off — source file byte offset, so you know exactly where to start reading 💅
• len — number of bytes to copy, the size of the vibe check 📏
• dst_off — destination file byte offset, where the copy lands on the other side 🌈

💜 DESCRIPTION 💜

So here's the tea: this function obtains a resume key for src_file, then issues FSCTL_SRV_COPYCHUNK_WRITE IOCTLs. It splits the request into chunks limited by tcon->max_*, because we are absolutely not trying to send one giant chaotic request, no cap. 🔥

⭐ RETURN ⭐

0 on success; negative errno on failure. Slay when it's 0, sad little errno when it's not. 😭

💀 SEE ALSO 💀

• Kernel file ./fs/smb/client/smb2ops.c
• calc_chunk_count(9)

xoxo, from ./fs/smb/client, dated October 2026, signing off as __smb2_copychunk_range(9) 💅💖✨