brelse(9)

✨ NAME ✨

Hey bestie, welcome to the brelse(9) page from the Kernel API Manual 🫶 — today's main character is brelse, and its whole job is releasing a buffer. Periodt.

🦋 SYNOPSIS 🦋

void brelse (struct buffer_head *bh );

🎀 ARGUMENTS 🎀

• bh — the buffer you're releasing. That's the argument, bestie, no hidden lore.

💅 DESCRIPTION 💅

Okay so brelse decrements a buffer_head's reference count. If bh is NULL, this function is a no-op — literally nothing happens, no crash, no drama, we love a safe little guard moment 💖.

Now for the slightly more unhinged part: if all buffers on a folio have zero reference count, are clean and unlocked, and if the folio is unlocked and not under writeback, then try_to_free_buffers may strip the buffers from the folio in preparation for freeing it. Sometimes — rarely — buffers are removed from a folio but it ends up not being freed, and buffers may later be reattached. Not me explaining the rare plot twist 😭 it's giving "almost freed but make it comeback" and honestly? Iconic.

🌈 CONTEXT 🌈

Any context. Like, genuinely any — no special mood required, go off 💅.

🔥 SEE ALSO 🔥

• Kernel file ./include/linux/buffer_head.h
• bforget(9)
• __bread(9)
• get_nth_bh(9)

Mwah 💖 this little page was brought to you by ./include/linux, dated October 2026, and yes — the manual page is brelse(9), no cap ✨