Commit 3821d768 authored by Martin K. Petersen's avatar Martin K. Petersen Committed by James Bottomley
Browse files

sd: Detect non-rotational devices 



Detect non-rotational devices and set the queue flag accordingly.

Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent ea09bcc9

drivers/scsi/sd.c

+26 −0
Original line number Diff line number Diff line
@@ -1794,6 +1794,29 @@ void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer) 
	return;

}



/**

 * sd_read_block_characteristics - Query block dev. characteristics

 * @disk: disk to query

 */

static void sd_read_block_characteristics(struct scsi_disk *sdkp)

{

	char *buffer;

	u16 rot;



	/* Block Device Characteristics VPD */

	buffer = scsi_get_vpd_page(sdkp->device, 0xb1);



	if (buffer == NULL)

		return;



	rot = get_unaligned_be16(&buffer[4]);



	if (rot == 1)

		queue_flag_set_unlocked(QUEUE_FLAG_NONROT, sdkp->disk->queue);



	kfree(buffer);

}



/**

 *	sd_revalidate_disk - called the first time a new disk is seen,

 *	performs disk spin up, read_capacity, etc.
@@ -1831,6 +1854,7 @@ static int sd_revalidate_disk(struct gendisk *disk) 
	 */

	if (sdkp->media_present) {

		sd_read_capacity(sdkp, buffer);

		sd_read_block_characteristics(sdkp);

		sd_read_write_protect_flag(sdkp, buffer);

		sd_read_cache_type(sdkp, buffer);

		sd_read_app_tag_own(sdkp, buffer);
@@ -1953,6 +1977,8 @@ static void sd_probe_async(void *data, async_cookie_t cookie) 
	add_disk(gd);

	sd_dif_config_host(sdkp);



	sd_revalidate_disk(gd);



	sd_printk(KERN_NOTICE, sdkp, "Attached SCSI %sdisk\n",

		  sdp->removable ? "removable " : "");

}