[PATCH 1/4] nvme: add a helper to check ctrl sgl support

[Chaitanya Kulkarni]

For various transports such as fc/tcp/pci it is common to check if
NVMe SGLs are supported or not by the controller.

In this preparation patch we add a helper to avoid the open coding of
such checks in the various transport.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
---
 drivers/nvme/host/nvme.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 1f397ecba16c..1aab74128d40 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -869,6 +869,14 @@ static inline void nvme_hwmon_exit(struct nvme_ctrl *ctrl)
 }
 #endif
 
+static inline bool nvme_ctrl_sgl_supported(struct nvme_ctrl *ctrl)
+{
+	if (!(ctrl->sgls & ((1 << 0) | (1 << 1))))
+		return true;
+
+	return false;
+}
+
 u32 nvme_command_effects(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
 			 u8 opcode);
 void nvme_execute_passthru_rq(struct request *rq);
-- 
2.22.1