ubi_calc_data_len(9)

✨ ubi_calc_data_len ✨

okay bestie, welcome to the ubi_calc_data_len(9) page from the Kernel API Manual 💅 this one's a lil kernel helper and honestly it's giving "quietly doing important work" energy 🎀

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🌸 NAME 🌸

ubi_calc_data_len — literally just calculates how much real data is stored in a buffer 🫶

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🦋 SYNOPSIS 🦋

int ubi_calc_data_len (const struct ubi_device *ubi , const void *buf ,
       int length );

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💖 ARGUMENTS 💖

• ubi — the UBI device description object, like the whole personality of the device ngl
• buf — a buffer holding the contents of the physical eraseblock, iykyk
• length — the length of that buffer, bestie. the actual size. the number 💅

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🎀 DESCRIPTION 🎀

so what this function does is it figures out how much "real data" is stored in buf and returns that length ✨ and the key thing here: continuous 0xFF bytes hanging out at the end of the buffer? yeah those do not count as "real data" 🙈 they're just filler, main character energy only applies to the actual content, periodt.

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👑 SEE ALSO 👑

• Kernel file ./drivers/mtd/ubi/misc.c
• ubi_check_volume(9)
• ubi_update_reserved(9)
• ubi_calculate_reserved(9)
• ubi_check_pattern(9)

all iconic, all worth a read, go check 'em out 🧚

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fr fr: that trailing 0xFF thing is the whole point of this function, don't forget it 💀

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and that's the whole page, bestie! this one's from ./drivers/mtd/ubi, dated October 2026 — logging off now, mwah 💜🌈⭐