nand_check_erased_buf(9)

💖 nand_check_erased_buf(9) 💖

okay so this little icon is straight outta the Kernel API Manual, and it's here to check if a buffer is giving erased-NAND energy ✨

🌸 NAME 🌸

nand_check_erased_buf — check if a buffer contains (almost) only 0xff data 💅

✨ SYNOPSIS ✨

int nand_check_erased_buf (void *buf , int len , int bitflips_threshold
);

🎀 ARGUMENTS 🎀

• buf — buffer to test, bestie 🫶
• len — buffer length
• bitflips_threshold — maximum number of bitflips

💅 DESCRIPTION 💅

so the whole vibe is: check if a buffer contains only 0xff, which means the underlying region has been erased and is ready to be programmed ✨ no cap.

The bitflips_threshold specify the maximum number of bitflips before considering the region is not erased 👑

💀 NOTE 💀

The logic of this function has been extracted from the memweight implementation, except that the nand_check_erased_buf function exits before testing the whole buffer if the number of bitflips exceed the bitflips_threshold value 😭

It returns a positive number of bitflips less than or equal to bitflips_threshold, or -ERROR_CODE for bitflips in excess of the threshold 💀

🦋 SEE ALSO 🦋

Kernel file ./drivers/mtd/nand/core.c — and here's the whole friend group:

• nand_check_erased_ecc_chunk(9)
• nanddev_isbad(9)
• nanddev_markbad(9)
• nanddev_isreserved(9)
• nanddev_erase(9)
• nanddev_mtd_erase(9)
• nanddev_mtd_max_bad_blocks(9)
• nanddev_get_ecc_engine(9)
• nanddev_put_ecc_engine(9)
• nanddev_find_ecc_configuration(9)
• nanddev_ecc_engine_init(9)
• nanddev_ecc_engine_cleanup(9)
• nanddev_init(9)
• nanddev_cleanup(9)

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later bestie — this one's from ./drivers/mtd/nand, October 2026 💅✨