The value we get from the low byte of the ATA_ID_SECTOR_SIZE word is not not a plain multiple, but the log of it, so fix the helper to give the correct answer. Without this we'll get an incorrect minimal I/O size in the block limits VPD page for 4k sector drives. Also change the return value of ata_id_logical_per_physical_sectors to u16 for the unlikely case of very large logical sectors. Signed-off-by: Christoph Hellwig <hch@xxxxxx> Index: linux-2.6/include/linux/ata.h =================================================================== --- linux-2.6.orig/include/linux/ata.h 2010-01-28 12:24:02.061016474 +0100 +++ linux-2.6/include/linux/ata.h 2010-01-28 13:26:59.270005271 +0100 @@ -647,9 +647,9 @@ static inline int ata_id_has_large_logic return id[ATA_ID_SECTOR_SIZE] & (1 << 13); } -static inline u8 ata_id_logical_per_physical_sectors(const u16 *id) +static inline u16 ata_id_logical_per_physical_sectors(const u16 *id) { - return id[ATA_ID_SECTOR_SIZE] & 0xf; + return 1 << (id[ATA_ID_SECTOR_SIZE] & 0xf); } static inline int ata_id_has_lba48(const u16 *id) -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html