Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fd4a3e28 authored by Tariq Toukan's avatar Tariq Toukan Committed by David S. Miller
Browse files

net/mlx4_core: Cleanup FMR unmapping flow 



Remove redundant and not essential operations in fmr unmap/free.
According to device spec, in FMR unmap it is sufficient to set
ownership bit to SW. This allows remapping afterwards.

Fixes: 8ad11fb6 ("IB/mlx4: Implement FMRs")
Signed-off-by: default avatarTariq Toukan <tariqt@mellanox.com>
Signed-off-by: default avatarMoshe Shemesh <moshe@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent dc484851

drivers/net/ethernet/mellanox/mlx4/mr.c

+21 −19
Original line number Diff line number Diff line
@@ -1103,30 +1103,16 @@ EXPORT_SYMBOL_GPL(mlx4_fmr_enable); 
void mlx4_fmr_unmap(struct mlx4_dev *dev, struct mlx4_fmr *fmr,

		    u32 *lkey, u32 *rkey)

{

	struct mlx4_cmd_mailbox *mailbox;

	int err;



	if (!fmr->maps)

		return;



	fmr->maps = 0;

	/* To unmap: it is sufficient to take back ownership from HW */

	*(u8 *)fmr->mpt = MLX4_MPT_STATUS_SW;



	mailbox = mlx4_alloc_cmd_mailbox(dev);

	if (IS_ERR(mailbox)) {

		err = PTR_ERR(mailbox);

		pr_warn("mlx4_ib: mlx4_alloc_cmd_mailbox failed (%d)\n", err);

		return;

	}

	/* Make sure MPT status is visible */

	wmb();



	err = mlx4_HW2SW_MPT(dev, NULL,

			     key_to_hw_index(fmr->mr.key) &

			     (dev->caps.num_mpts - 1));

	mlx4_free_cmd_mailbox(dev, mailbox);

	if (err) {

		pr_warn("mlx4_ib: mlx4_HW2SW_MPT failed (%d)\n", err);

		return;

	}

	fmr->mr.enabled = MLX4_MPT_EN_SW;

	fmr->maps = 0;

}

EXPORT_SYMBOL_GPL(mlx4_fmr_unmap);
@@ -1136,6 +1122,22 @@ int mlx4_fmr_free(struct mlx4_dev *dev, struct mlx4_fmr *fmr) 


	if (fmr->maps)

		return -EBUSY;

	if (fmr->mr.enabled == MLX4_MPT_EN_HW) {

		/* In case of FMR was enabled and unmapped

		 * make sure to give ownership of MPT back to HW

		 * so HW2SW_MPT command will success.

		 */

		*(u8 *)fmr->mpt = MLX4_MPT_STATUS_SW;

		/* Make sure MPT status is visible before changing MPT fields */

		wmb();

		fmr->mpt->length = 0;

		fmr->mpt->start  = 0;

		/* Make sure MPT data is visible after changing MPT status */

		wmb();

		*(u8 *)fmr->mpt = MLX4_MPT_STATUS_HW;

		/* make sure MPT status is visible */

		wmb();

	}



	ret = mlx4_mr_free(dev, &fmr->mr);

	if (ret)