[PATCH AUTOSEL 6.1 19/29] nvme: introduce helper function to get ctrl state

[Sasha Levin <sashal@kernel.org>]

From: Keith Busch <kbusch@kernel.org>

[ Upstream commit 5c687c287c46fadb14644091823298875a5216aa ]

The controller state is typically written by another CPU, so reading it
should ensure no optimizations are taken. This is a repeated pattern in
the driver, so start with adding a convenience function that returns the
controller state with READ_ONCE().

Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/nvme/host/nvme.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 69f9e69208f68..8b50b56b8ee31 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -377,6 +377,11 @@ struct nvme_ctrl {
 	enum nvme_dctype dctype;
 };
 
+static inline enum nvme_ctrl_state nvme_ctrl_state(struct nvme_ctrl *ctrl)
+{
+	return READ_ONCE(ctrl->state);
+}
+
 enum nvme_iopolicy {
 	NVME_IOPOLICY_NUMA,
 	NVME_IOPOLICY_RR,
-- 
2.42.0