get_bbt_block(9)

💖 get_bbt_block(9) 💖

okay so bestie, we're in the Kernel API Manual today and this one is a little NAND-flash baddie called get_bbt_block. she's lowkey the one who finds you a place to live. let's get into it 🫶

---

✨ NAME ✨

get_bbt_block — get the first valid eraseblock suitable to store a BBT 🌸

---

✨ SYNOPSIS ✨

int get_bbt_block (struct nand_chip *this , struct nand_bbt_descr *td ,
struct nand_bbt_descr *md , int chip );

---

✨ ARGUMENTS ✨

• this — the NAND device itself, the main character 💅
• td — the BBT description, aka the vibe info for the BBT
• md — the mirror BBT descriptor (yes girl, she has a mirror version too 🪞)
• chip — the CHIP selector, so we know which chip we're talking about

---

🌈 DESCRIPTION 🌈

so this function returns a positive block number pointing at a valid eraseblock that's suitable to store a BBT — meaning it's inside the range reserved for BBT, no cap ✨. if all the blocks are already used or marked bad, she hits you with -ENOSPC and it's giving "no space, sorry bestie" 😭.

and here's the cute part: if td->pages[chip] was already pointing to a valid block, we just re-use it 🎀. she's not gonna do extra work for no reason. otherwise, we go searching for the next valid one, like a little scavenger hunt but for eraseblocks 🦋⭐

ngl, -ENOSPC means everything's taken or marked bad — no block for you, and that's just how it is 💀

---

💜 SEE ALSO 💜

Kernel file ./drivers/mtd/nand/raw/nand_bbt.c, plus the whole friend group:

check_pattern(9), check_short_pattern(9), add_marker_len(9), read_bbt(9), read_abs_bbt(9), scan_read_oob(9), read_abs_bbts(9), create_bbt(9), search_bbt(9), search_read_bbts(9), mark_bbt_block_bad(9), write_bbt(9), nand_memory_bbt(9), check_create(9), nand_update_bbt(9), mark_bbt_region(9), verify_bbt_descr(9), nand_scan_bbt(9), nand_create_badblock_pattern(9), nand_create_bbt(9), nand_isreserved_bbt(9), nand_isbad_bbt(9), nand_markbad_bbt(9) 👑

---

and that's the whole page, icon. straight out of ./drivers/mtd/nand/raw, dated October 2026 — periodt, go read the source, ily, bye 🧚💖