target/sbc: Only expose PI read_cap16 bits when supported by fabric

Only expose the PI protection type bits in READ_CAPACITY_16
if the session + fabric support DIX PASS operations.
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_sbc.c

@@ -89,6 +89,7 @@ static sense_reason_t
 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
 {
 	struct se_device *dev = cmd->se_dev;
+	struct se_session *sess = cmd->se_sess;
 	unsigned char *rbuf;
 	unsigned char buf[32];
 	unsigned long long blocks = dev->transport->get_blocks(dev);
@@ -109,8 +110,10 @@ sbc_emulate_readcapacity_16(struct se_cmd *cmd)
 	/*
 	 * Set P_TYPE and PROT_EN bits for DIF support
 	 */
+	if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
 		if (dev->dev_attrib.pi_prot_type)
 			buf[12] = (dev->dev_attrib.pi_prot_type - 1) << 1 | 0x1;
+	}
 
 	if (dev->transport->get_lbppbe)
 		buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;