From f7acede65d6b65919aee5b6a360a17cedb11f2f7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 28 Jan 2010 13:30:11 +0100 Subject: [PATCH] libata: fix ata_id_logical_per_physical_sectors 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 Signed-off-by: Jeff Garzik --- include/linux/ata.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/ata.h b/include/linux/ata.h index 38a6948ce0c..20f31567cce 100644 --- a/include/linux/ata.h +++ b/include/linux/ata.h @@ -647,9 +647,9 @@ static inline int ata_id_has_large_logical_sectors(const u16 *id) 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) -- 2.20.1