diff options
| author | Martin K. Petersen <martin.petersen@oracle.com> | 2009-05-23 11:43:39 -0400 |
|---|---|---|
| committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2009-06-21 10:52:38 -0500 |
| commit | d11b6916961d6ec7d7215332cbbe9feec086721d (patch) | |
| tree | 152bdf47fbf1cc1604e79748655dfddfe8f74ce7 /drivers/scsi/sd.c | |
| parent | 3821d768912a47ddbd6cab52943a8284df88003c (diff) | |
sd: Block limits VPD support
Query the block limits VPD page and adjust queue minimum and optimal I/O
sizes.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Diffstat (limited to 'drivers/scsi/sd.c')
| -rw-r--r-- | drivers/scsi/sd.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 2148d659c28..e4ef11af18a 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1795,6 +1795,29 @@ void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer) } /** + * sd_read_block_limits - Query disk device for preferred I/O sizes. + * @disk: disk to query + */ +static void sd_read_block_limits(struct scsi_disk *sdkp) +{ + unsigned int sector_sz = sdkp->device->sector_size; + char *buffer; + + /* Block Limits VPD */ + buffer = scsi_get_vpd_page(sdkp->device, 0xb0); + + if (buffer == NULL) + return; + + blk_queue_io_min(sdkp->disk->queue, + get_unaligned_be16(&buffer[6]) * sector_sz); + blk_queue_io_opt(sdkp->disk->queue, + get_unaligned_be32(&buffer[12]) * sector_sz); + + kfree(buffer); +} + +/** * sd_read_block_characteristics - Query block dev. characteristics * @disk: disk to query */ @@ -1854,6 +1877,7 @@ static int sd_revalidate_disk(struct gendisk *disk) */ if (sdkp->media_present) { sd_read_capacity(sdkp, buffer); + sd_read_block_limits(sdkp); sd_read_block_characteristics(sdkp); sd_read_write_protect_flag(sdkp, buffer); sd_read_cache_type(sdkp, buffer); |