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Merge branch 'for-linus' of git://git.infradead.org/ubi-2.6
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* 'for-linus' of git://git.infradead.org/ubi-2.6:
  Revert "UBI: use mtd->writebufsize to set minimal I/O unit size"
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Linus Torvalds committed Jan 31, 2011
2 parents 54e74b8 + 3a0592b commit 70d1f36
Showing 1 changed file with 1 addition and 27 deletions.
28 changes: 1 addition & 27 deletions drivers/mtd/ubi/build.c
Original file line number Diff line number Diff line change
Expand Up @@ -672,33 +672,7 @@ static int io_init(struct ubi_device *ubi)
ubi->nor_flash = 1;
}

/*
* Set UBI min. I/O size (@ubi->min_io_size). We use @mtd->writebufsize
* for these purposes, not @mtd->writesize. At the moment this does not
* matter for NAND, because currently @mtd->writebufsize is equivalent to
* @mtd->writesize for all NANDs. However, some CFI NOR flashes may
* have @mtd->writebufsize which is multiple of @mtd->writesize.
*
* The reason we use @mtd->writebufsize for @ubi->min_io_size is that
* UBI and UBIFS recovery algorithms rely on the fact that if there was
* an unclean power cut, then we can find offset of the last corrupted
* node, align the offset to @ubi->min_io_size, read the rest of the
* eraseblock starting from this offset, and check whether there are
* only 0xFF bytes. If yes, then we are probably dealing with a
* corruption caused by a power cut, if not, then this is probably some
* severe corruption.
*
* Thus, we have to use the maximum write unit size of the flash, which
* is @mtd->writebufsize, because @mtd->writesize is the minimum write
* size, not the maximum.
*/
if (ubi->mtd->type == MTD_NANDFLASH)
ubi_assert(ubi->mtd->writebufsize == ubi->mtd->writesize);
else if (ubi->mtd->type == MTD_NORFLASH)
ubi_assert(ubi->mtd->writebufsize % ubi->mtd->writesize == 0);

ubi->min_io_size = ubi->mtd->writebufsize;

ubi->min_io_size = ubi->mtd->writesize;
ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;

/*
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