| Message ID | 20100128104234.GA25693@lst.de |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
Hello. Christoph Hellwig wrote: > 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. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > > Index: linux-2.6/include/linux/ata.h > =================================================================== > --- linux-2.6.orig/include/linux/ata.h 2010-01-28 11:17:41.968003842 +0100 > +++ linux-2.6/include/linux/ata.h 2010-01-28 11:20:02.355268610 +0100 > @@ -649,7 +649,7 @@ static inline int ata_id_has_large_logic > > static inline u8 ata_id_logical_per_physical_sectors(const u16 *id) > { > - return id[ATA_ID_SECTOR_SIZE] & 0xf; > + return 1 << (id[ATA_ID_SECTOR_SIZE] & 0xf); > Will this still fit into u8? WBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jan 28, 2010 at 01:56:21PM +0300, Sergei Shtylyov wrote: > > static inline u8 ata_id_logical_per_physical_sectors(const u16 *id) > > { > >- return id[ATA_ID_SECTOR_SIZE] & 0xf; > >+ return 1 << (id[ATA_ID_SECTOR_SIZE] & 0xf); > > > > Will this still fit into u8? Right now the only value we get in practice is 8 for 4k sector drivers which still fits fine into an u8. But it might indeed be safer to use a large value. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Index: linux-2.6/include/linux/ata.h =================================================================== --- linux-2.6.orig/include/linux/ata.h 2010-01-28 11:17:41.968003842 +0100 +++ linux-2.6/include/linux/ata.h 2010-01-28 11:20:02.355268610 +0100 @@ -649,7 +649,7 @@ static inline int ata_id_has_large_logic static inline u8 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)
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. Signed-off-by: Christoph Hellwig <hch@lst.de> -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html