nvmet: expose support for fabrics SQ flow control disable in treq

Technical Proposal introduces an indication for SQ flow control
disable support. Expose it since we are able to operate in this mode.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/nvme/target/configfs.c

@@ -1214,6 +1214,7 @@ static struct config_group *nvmet_ports_make(struct config_group *group,
 	port->inline_data_size = -1;	/* < 0 == let the transport choose */
 
 	port->disc_addr.portid = cpu_to_le16(portid);
+	port->disc_addr.treq = NVMF_TREQ_DISABLE_SQFLOW;
 	config_group_init_type_name(&port->group, name, &nvmet_port_type);
 
 	config_group_init_type_name(&port->subsys_group,

include/linux/nvme.h

@@ -63,6 +63,8 @@ enum {
 	NVMF_TREQ_NOT_REQUIRED	= 2,		/* Not Required */
 #define NVME_TREQ_SECURE_CHANNEL_MASK \
 	(NVMF_TREQ_REQUIRED | NVMF_TREQ_NOT_REQUIRED)
+
+	NVMF_TREQ_DISABLE_SQFLOW = (1 << 2),	/* Supports SQ flow control disable */
 };
 
 /* RDMA QP Service Type codes for Discovery Log Page entry TSAS