Commit 9e06688e authored by Martin K. Petersen's avatar Martin K. Petersen Committed by James Bottomley
Browse files

[SCSI] sd: Correctly handle all combinations of DIF and DIX 



The old detection code couldn't handle all possible combinations of
DIX and DIF.  This version does, giving priority to DIX if the
controller is capable.

Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent be922f47

drivers/scsi/sd.c

+2 −1
Original line number Diff line number Diff line
@@ -575,7 +575,8 @@ static int sd_prep_fn(struct request_queue *q, struct request *rq) 


	/* If DIF or DIX is enabled, tell HBA how to handle request */

	if (host_dif || scsi_prot_sg_count(SCpnt))

		sd_dif_op(SCpnt, sdkp->protection_type, scsi_prot_sg_count(SCpnt));

		sd_dif_op(SCpnt, host_dif, scsi_prot_sg_count(SCpnt),

			  sdkp->protection_type);



	/*

	 * We shouldn't disconnect in the middle of a sector, so with a dumb

drivers/scsi/sd.h

+1 −1
Original line number Diff line number Diff line
@@ -99,7 +99,7 @@ struct sd_dif_tuple { 


#if defined(CONFIG_BLK_DEV_INTEGRITY)



extern void sd_dif_op(struct scsi_cmnd *, unsigned int, unsigned int);

extern void sd_dif_op(struct scsi_cmnd *, unsigned int, unsigned int, unsigned int);

extern void sd_dif_config_host(struct scsi_disk *);

extern int sd_dif_prepare(struct request *rq, sector_t, unsigned int);

extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);

drivers/scsi/sd_dif.c

+20 −17
Original line number Diff line number Diff line
@@ -311,24 +311,26 @@ void sd_dif_config_host(struct scsi_disk *sdkp) 
	struct scsi_device *sdp = sdkp->device;

	struct gendisk *disk = sdkp->disk;

	u8 type = sdkp->protection_type;

	int dif, dix;



	/* If this HBA doesn't support DIX, resort to normal I/O or DIF */

	if (scsi_host_dix_capable(sdp->host, type) == 0) {

	dif = scsi_host_dif_capable(sdp->host, type);

	dix = scsi_host_dix_capable(sdp->host, type);



		if (type == SD_DIF_TYPE0_PROTECTION)

			return;



		if (scsi_host_dif_capable(sdp->host, type) == 0) {

			sd_printk(KERN_INFO, sdkp, "Type %d protection " \

				  "unsupported by HBA. Disabling DIF.\n", type);

			return;

	if (!dix && scsi_host_dix_capable(sdp->host, 0)) {

		dif = 0; dix = 1;

	}



		sd_printk(KERN_INFO, sdkp, "Enabling DIF Type %d protection\n",

			  type);

	if (type) {

		if (dif)

			sd_printk(KERN_INFO, sdkp,

				  "Enabling DIF Type %d protection\n", type);

		else

			sd_printk(KERN_INFO, sdkp,

				  "Disabling DIF Type %d protection\n", type);

	}



	if (!dix)

		return;

	}



	/* Enable DMA of protection information */

	if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
@@ -343,10 +345,10 @@ void sd_dif_config_host(struct scsi_disk *sdkp) 
			blk_integrity_register(disk, &dif_type1_integrity_crc);



	sd_printk(KERN_INFO, sdkp,

		  "Enabling %s integrity protection\n", disk->integrity->name);

		  "Enabling DIX %s protection\n", disk->integrity->name);



	/* Signal to block layer that we support sector tagging */

	if (type && sdkp->ATO) {

	if (dif && type && sdkp->ATO) {

		if (type == SD_DIF_TYPE3_PROTECTION)

			disk->integrity->tag_size = sizeof(u16) + sizeof(u32);

		else
@@ -360,7 +362,7 @@ void sd_dif_config_host(struct scsi_disk *sdkp) 
/*

 * DIF DMA operation magic decoder ring.

 */

void sd_dif_op(struct scsi_cmnd *scmd, unsigned int dif, unsigned int dix)

void sd_dif_op(struct scsi_cmnd *scmd, unsigned int dif, unsigned int dix, unsigned int type)

{

	int csum_convert, prot_op;
@@ -405,7 +407,8 @@ void sd_dif_op(struct scsi_cmnd *scmd, unsigned int dif, unsigned int dix) 
	}



	scsi_set_prot_op(scmd, prot_op);

	scsi_set_prot_type(scmd, dif);

	if (dif)

		scsi_set_prot_type(scmd, type);

}



/*