Commit 14e426bf authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

devlink: hold the instance lock during eswitch_mode callbacks 



Make the devlink core hold the instance lock during eswitch_mode
callbacks. Cheat in case of mlx5 (see the cover letter).

Reviewed-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Reviewed-by: default avatarJiri Pirko <jiri@nvidia.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent aff3a925

drivers/net/ethernet/broadcom/bnxt/bnxt_vfr.c

+6 −16
Original line number Diff line number Diff line
@@ -559,44 +559,34 @@ int bnxt_dl_eswitch_mode_set(struct devlink *devlink, u16 mode, 
			     struct netlink_ext_ack *extack)

{

	struct bnxt *bp = bnxt_get_bp_from_dl(devlink);

	int rc = 0;



	devl_lock(devlink);

	if (bp->eswitch_mode == mode) {

		netdev_info(bp->dev, "already in %s eswitch mode\n",

			    mode == DEVLINK_ESWITCH_MODE_LEGACY ?

			    "legacy" : "switchdev");

		rc = -EINVAL;

		goto done;

		return -EINVAL;

	}



	switch (mode) {

	case DEVLINK_ESWITCH_MODE_LEGACY:

		bnxt_vf_reps_destroy(bp);

		break;

		return 0;



	case DEVLINK_ESWITCH_MODE_SWITCHDEV:

		if (bp->hwrm_spec_code < 0x10803) {

			netdev_warn(bp->dev, "FW does not support SRIOV E-Switch SWITCHDEV mode\n");

			rc = -ENOTSUPP;

			goto done;

			return -ENOTSUPP;

		}



		if (pci_num_vf(bp->pdev) == 0) {

			netdev_info(bp->dev, "Enable VFs before setting switchdev mode\n");

			rc = -EPERM;

			goto done;

			return -EPERM;

		}

		rc = bnxt_vf_reps_create(bp);

		break;

		return bnxt_vf_reps_create(bp);



	default:

		rc = -EINVAL;

		goto done;

		return -EINVAL;

	}

done:

	devl_unlock(devlink);

	return rc;

}



#endif

drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c

+42 −12
Original line number Diff line number Diff line
@@ -3337,6 +3337,27 @@ static int eswitch_devlink_esw_mode_check(const struct mlx5_eswitch *esw) 
		!mlx5_core_is_ecpf_esw_manager(esw->dev)) ? -EOPNOTSUPP : 0;

}



/* FIXME: devl_unlock() followed by devl_lock() inside driver callback

 * is never correct and prone to races. It's a transitional workaround,

 * never repeat this pattern.

 *

 * This code MUST be fixed before removing devlink_mutex as it is safe

 * to do only because of that mutex.

 */

static void mlx5_eswtich_mode_callback_enter(struct devlink *devlink,

					     struct mlx5_eswitch *esw)

{

	devl_unlock(devlink);

	down_write(&esw->mode_lock);

}



static void mlx5_eswtich_mode_callback_exit(struct devlink *devlink,

					    struct mlx5_eswitch *esw)

{

	up_write(&esw->mode_lock);

	devl_lock(devlink);

}



int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,

				  struct netlink_ext_ack *extack)

{
@@ -3351,6 +3372,15 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode, 
	if (esw_mode_from_devlink(mode, &mlx5_mode))

		return -EINVAL;



	/* FIXME: devl_unlock() followed by devl_lock() inside driver callback

	 * is never correct and prone to races. It's a transitional workaround,

	 * never repeat this pattern.

	 *

	 * This code MUST be fixed before removing devlink_mutex as it is safe

	 * to do only because of that mutex.

	 */

	devl_unlock(devlink);



	mlx5_lag_disable_change(esw->dev);

	err = mlx5_esw_try_lock(esw);

	if (err < 0) {
@@ -3381,6 +3411,7 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode, 
	mlx5_esw_unlock(esw);

enable_lag:

	mlx5_lag_enable_change(esw->dev);

	devl_lock(devlink);

	return err;

}
@@ -3393,14 +3424,14 @@ int mlx5_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode) 
	if (IS_ERR(esw))

		return PTR_ERR(esw);



	down_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_enter(devlink, esw);

	err = eswitch_devlink_esw_mode_check(esw);

	if (err)

		goto unlock;



	err = esw_mode_to_devlink(esw->mode, mode);

unlock:

	up_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_exit(devlink, esw);

	return err;

}
@@ -3447,7 +3478,7 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode, 
	if (IS_ERR(esw))

		return PTR_ERR(esw);



	down_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_enter(devlink, esw);

	err = eswitch_devlink_esw_mode_check(esw);

	if (err)

		goto out;
@@ -3484,11 +3515,11 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode, 
		goto out;



	esw->offloads.inline_mode = mlx5_mode;

	up_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_exit(devlink, esw);

	return 0;



out:

	up_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_exit(devlink, esw);

	return err;

}
@@ -3501,14 +3532,14 @@ int mlx5_devlink_eswitch_inline_mode_get(struct devlink *devlink, u8 *mode) 
	if (IS_ERR(esw))

		return PTR_ERR(esw);



	down_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_enter(devlink, esw);

	err = eswitch_devlink_esw_mode_check(esw);

	if (err)

		goto unlock;



	err = esw_inline_mode_to_devlink(esw->offloads.inline_mode, mode);

unlock:

	up_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_exit(devlink, esw);

	return err;

}
@@ -3524,7 +3555,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink, 
	if (IS_ERR(esw))

		return PTR_ERR(esw);



	down_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_enter(devlink, esw);

	err = eswitch_devlink_esw_mode_check(esw);

	if (err)

		goto unlock;
@@ -3570,7 +3601,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink, 
	}



unlock:

	up_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_exit(devlink, esw);

	return err;

}
@@ -3584,15 +3615,14 @@ int mlx5_devlink_eswitch_encap_mode_get(struct devlink *devlink, 
	if (IS_ERR(esw))

		return PTR_ERR(esw);





	down_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_enter(devlink, esw);

	err = eswitch_devlink_esw_mode_check(esw);

	if (err)

		goto unlock;



	*encap = esw->offloads.encap;

unlock:

	up_write(&esw->mode_lock);

	mlx5_eswtich_mode_callback_exit(devlink, esw);

	return err;

}

drivers/net/ethernet/netronome/nfp/nfp_devlink.c

+1 −6
Original line number Diff line number Diff line
@@ -144,13 +144,8 @@ static int nfp_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode, 
					struct netlink_ext_ack *extack)

{

	struct nfp_pf *pf = devlink_priv(devlink);

	int ret;



	devl_lock(devlink);

	ret = nfp_app_eswitch_mode_set(pf->app, mode);

	devl_unlock(devlink);



	return ret;

	return nfp_app_eswitch_mode_set(pf->app, mode);

}



static const struct nfp_devlink_versions_simple {

drivers/net/netdevsim/dev.c

+5 −11
Original line number Diff line number Diff line
@@ -615,22 +615,16 @@ static int nsim_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode, 
					 struct netlink_ext_ack *extack)

{

	struct nsim_dev *nsim_dev = devlink_priv(devlink);

	int err = 0;



	devl_lock(devlink);

	if (mode == nsim_dev->esw_mode)

		goto unlock;

		return 0;



	if (mode == DEVLINK_ESWITCH_MODE_LEGACY)

		err = nsim_esw_legacy_enable(nsim_dev, extack);

	else if (mode == DEVLINK_ESWITCH_MODE_SWITCHDEV)

		err = nsim_esw_switchdev_enable(nsim_dev, extack);

	else

		err = -EINVAL;

		return nsim_esw_legacy_enable(nsim_dev, extack);

	if (mode == DEVLINK_ESWITCH_MODE_SWITCHDEV)

		return nsim_esw_switchdev_enable(nsim_dev, extack);



unlock:

	devl_unlock(devlink);

	return err;

	return -EINVAL;

}



static int nsim_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode)

net/core/devlink.c

+0 −6
Original line number Diff line number Diff line
@@ -2868,15 +2868,11 @@ static int devlink_rate_nodes_check(struct devlink *devlink, u16 mode, 
{

	struct devlink_rate *devlink_rate;



	/* Take the lock to sync with destroy */

	mutex_lock(&devlink->lock);

	list_for_each_entry(devlink_rate, &devlink->rate_list, list)

		if (devlink_rate_is_node(devlink_rate)) {

			mutex_unlock(&devlink->lock);

			NL_SET_ERR_MSG_MOD(extack, "Rate node(s) exists.");

			return -EBUSY;

		}

	mutex_unlock(&devlink->lock);

	return 0;

}
@@ -8735,14 +8731,12 @@ static const struct genl_small_ops devlink_nl_ops[] = { 
		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,

		.doit = devlink_nl_cmd_eswitch_get_doit,

		.flags = GENL_ADMIN_PERM,

		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,

	},

	{

		.cmd = DEVLINK_CMD_ESWITCH_SET,

		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,

		.doit = devlink_nl_cmd_eswitch_set_doit,

		.flags = GENL_ADMIN_PERM,

		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,

	},

	{

		.cmd = DEVLINK_CMD_DPIPE_TABLE_GET,