mlx4_ib: unmap FMR should update MPT status to 0xF

ConnectX PRM: To unmap the FMR (prior to issuing
the SYNC_TPT command), set the status field to
0xF(MLX4_MPT_STATUS_SW). The status is only a part
of the byte, and the software is allowed to write
zeroes to the rest of the byte (to avoid a
read-modify-write operation).

Set the status field to 0(MLX4_MPT_STATUS_HW) in
free FMR code.

Orabug: 18801967

Signed-off-by: Saeed Mahameed <[email protected]>
Signed-off-by: Mukesh Kacker <[email protected]>
Acked-by: Konrad Rzeszutek Wilk <[email protected]>
(cherry picked from commit 1ee0f6d80889fa47c2136654477d14340fa94e72)
Signed-off-by: Jerry Snitselaar <[email protected]>

Author: Mukesh Kacker

drivers/net/mlx4/mr.c

@@ -1222,6 +1222,10 @@ void mlx4_fmr_unmap(struct mlx4_dev *dev, struct mlx4_fmr *fmr,
 
 	fmr->maps = 0;
 
+	*(u8 *)fmr->mpt = MLX4_MPT_STATUS_SW;
+	/* Make sure MPT status is visible */
+	wmb();
+
 	fmr->mr.enabled = MLX4_MR_EN_SW;
 }
 EXPORT_SYMBOL_GPL(mlx4_fmr_unmap);
@@ -1231,6 +1235,10 @@ int mlx4_fmr_free(struct mlx4_dev *dev, struct mlx4_fmr *fmr)
 	if (fmr->maps)
 		return -EBUSY;
 
+	*(u8 *)fmr->mpt = MLX4_MPT_STATUS_HW;
+	/* Make sure MPT status is visible */
+	wmb();
+
 	mlx4_mr_free(dev, &fmr->mr);
 	fmr->mr.enabled = MLX4_MR_DISABLED;