drivers/net/ethernet/mellanox/mlx5/core/sriov.c - linux - Git at Google

 /*
  * Copyright (c) 2014, Mellanox Technologies inc.  All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * OpenIB.org BSD license below:
  *
  *     Redistribution and use in source and binary forms, with or
  *     without modification, are permitted provided that the following
  *     conditions are met:
  *
  *      - Redistributions of source code must retain the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer.
  *
  *      - Redistributions in binary form must reproduce the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer in the documentation and/or other materials
  *        provided with the distribution.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include <linux/pci.h>
 #include <linux/mlx5/driver.h>
 #include <linux/mlx5/vport.h>
 #include "mlx5_core.h"
 #include "mlx5_irq.h"
 #include "eswitch.h"

 static int sriov_restore_guids(struct mlx5_core_dev *dev, int vf)
 {
 	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 	struct mlx5_hca_vport_context *in;
 	int err = 0;

 	/* Restore sriov guid and policy settings */
 	if (sriov->vfs_ctx[vf].node_guid ||
 	    sriov->vfs_ctx[vf].port_guid ||
 	    sriov->vfs_ctx[vf].policy != MLX5_POLICY_INVALID) {
 		in = kzalloc(sizeof(*in), GFP_KERNEL);
 		if (!in)
 			return -ENOMEM;

 		in->node_guid = sriov->vfs_ctx[vf].node_guid;
 		in->port_guid = sriov->vfs_ctx[vf].port_guid;
 		in->policy = sriov->vfs_ctx[vf].policy;
 		in->field_select =
 			!!(in->port_guid) * MLX5_HCA_VPORT_SEL_PORT_GUID |
 			!!(in->node_guid) * MLX5_HCA_VPORT_SEL_NODE_GUID |
 			!!(in->policy) * MLX5_HCA_VPORT_SEL_STATE_POLICY;

 		err = mlx5_core_modify_hca_vport_context(dev, 1, 1, vf + 1, in);
 		if (err)
 			mlx5_core_warn(dev, "modify vport context failed, unable to restore VF %d settings\n", vf);

 		kfree(in);
 	}

 	return err;
 }

 static int mlx5_device_enable_sriov(struct mlx5_core_dev *dev, int num_vfs)
 {
 	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 	int err, vf, num_msix_count;

 	if (!MLX5_ESWITCH_MANAGER(dev))
 		goto enable_vfs_hca;

 	err = mlx5_eswitch_enable(dev->priv.eswitch, num_vfs);
 	if (err) {
 		mlx5_core_warn(dev,
 			       "failed to enable eswitch SRIOV (%d)\n", err);
 		return err;
 	}

 enable_vfs_hca:
 	num_msix_count = mlx5_get_default_msix_vec_count(dev, num_vfs);
 	for (vf = 0; vf < num_vfs; vf++) {
 		/* Notify the VF before its enablement to let it set
 		 * some stuff.
 		 */
 		blocking_notifier_call_chain(&sriov->vfs_ctx[vf].notifier,
 					     MLX5_PF_NOTIFY_ENABLE_VF, dev);
 		err = mlx5_core_enable_hca(dev, vf + 1);
 		if (err) {
 			mlx5_core_warn(dev, "failed to enable VF %d (%d)\n", vf, err);
 			continue;
 		}

 		err = mlx5_set_msix_vec_count(dev, vf + 1, num_msix_count);
 		if (err) {
 			mlx5_core_warn(dev,
 				       "failed to set MSI-X vector counts VF %d, err %d\n",
 				       vf, err);
 			continue;
 		}

 		sriov->vfs_ctx[vf].enabled = 1;
 		if (MLX5_CAP_GEN(dev, port_type) == MLX5_CAP_PORT_TYPE_IB) {
 			err = sriov_restore_guids(dev, vf);
 			if (err) {
 				mlx5_core_warn(dev,
 					       "failed to restore VF %d settings, err %d\n",
 					       vf, err);
 				continue;
 			}
 		}
 		mlx5_core_dbg(dev, "successfully enabled VF* %d\n", vf);
 	}

 	return 0;
 }

 static void
 mlx5_device_disable_sriov(struct mlx5_core_dev *dev, int num_vfs, bool clear_vf)
 {
 	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 	int err;
 	int vf;

 	for (vf = num_vfs - 1; vf >= 0; vf--) {
 		if (!sriov->vfs_ctx[vf].enabled)
 			continue;
 		/* Notify the VF before its disablement to let it clean
 		 * some resources.
 		 */
 		blocking_notifier_call_chain(&sriov->vfs_ctx[vf].notifier,
 					     MLX5_PF_NOTIFY_DISABLE_VF, dev);
 		err = mlx5_core_disable_hca(dev, vf + 1);
 		if (err) {
 			mlx5_core_warn(dev, "failed to disable VF %d\n", vf);
 			continue;
 		}
 		sriov->vfs_ctx[vf].enabled = 0;
 	}

 	mlx5_eswitch_disable_sriov(dev->priv.eswitch, clear_vf);

 	if (mlx5_wait_for_pages(dev, &dev->priv.vfs_pages))
 		mlx5_core_warn(dev, "timeout reclaiming VFs pages\n");
 }

 static int mlx5_sriov_enable(struct pci_dev *pdev, int num_vfs)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
 	struct devlink *devlink = priv_to_devlink(dev);
 	int err;

 	devl_lock(devlink);
 	err = mlx5_device_enable_sriov(dev, num_vfs);
 	devl_unlock(devlink);
 	if (err) {
 		mlx5_core_warn(dev, "mlx5_device_enable_sriov failed : %d\n", err);
 		return err;
 	}

 	err = pci_enable_sriov(pdev, num_vfs);
 	if (err) {
 		mlx5_core_warn(dev, "pci_enable_sriov failed : %d\n", err);
 		mlx5_device_disable_sriov(dev, num_vfs, true);
 	}
 	return err;
 }

 void mlx5_sriov_disable(struct pci_dev *pdev)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
 	struct devlink *devlink = priv_to_devlink(dev);
 	int num_vfs = pci_num_vf(dev->pdev);

 	pci_disable_sriov(pdev);
 	devl_lock(devlink);
 	mlx5_device_disable_sriov(dev, num_vfs, true);
 	devl_unlock(devlink);
 }

 int mlx5_core_sriov_configure(struct pci_dev *pdev, int num_vfs)
 {
 	struct mlx5_core_dev *dev  = pci_get_drvdata(pdev);
 	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 	int err = 0;

 	mlx5_core_dbg(dev, "requested num_vfs %d\n", num_vfs);

 	if (num_vfs)
 		err = mlx5_sriov_enable(pdev, num_vfs);
 	else
 		mlx5_sriov_disable(pdev);

 	if (!err)
 		sriov->num_vfs = num_vfs;
 	return err ? err : num_vfs;
 }

 int mlx5_core_sriov_set_msix_vec_count(struct pci_dev *vf, int msix_vec_count)
 {
 	struct pci_dev *pf = pci_physfn(vf);
 	struct mlx5_core_sriov *sriov;
 	struct mlx5_core_dev *dev;
 	int num_vf_msix, id;

 	dev = pci_get_drvdata(pf);
 	num_vf_msix = MLX5_CAP_GEN_MAX(dev, num_total_dynamic_vf_msix);
 	if (!num_vf_msix)
 		return -EOPNOTSUPP;

 	if (!msix_vec_count)
 		msix_vec_count =
 			mlx5_get_default_msix_vec_count(dev, pci_num_vf(pf));

 	sriov = &dev->priv.sriov;
 	id = pci_iov_vf_id(vf);
 	if (id < 0 || !sriov->vfs_ctx[id].enabled)
 		return -EINVAL;

 	return mlx5_set_msix_vec_count(dev, id + 1, msix_vec_count);
 }

 int mlx5_sriov_attach(struct mlx5_core_dev *dev)
 {
 	if (!mlx5_core_is_pf(dev) || !pci_num_vf(dev->pdev))
 		return 0;

 	/* If sriov VFs exist in PCI level, enable them in device level */
 	return mlx5_device_enable_sriov(dev, pci_num_vf(dev->pdev));
 }

 void mlx5_sriov_detach(struct mlx5_core_dev *dev)
 {
 	if (!mlx5_core_is_pf(dev))
 		return;

 	mlx5_device_disable_sriov(dev, pci_num_vf(dev->pdev), false);
 }

 static u16 mlx5_get_max_vfs(struct mlx5_core_dev *dev)
 {
 	u16 host_total_vfs;
 	const u32 *out;

 	if (mlx5_core_is_ecpf_esw_manager(dev)) {
 		out = mlx5_esw_query_functions(dev);

 		/* Old FW doesn't support getting total_vfs from esw func
 		 * but supports getting it from pci_sriov.
 		 */
 		if (IS_ERR(out))
 			goto done;
 		host_total_vfs = MLX5_GET(query_esw_functions_out, out,
 					  host_params_context.host_total_vfs);
 		kvfree(out);
 		if (host_total_vfs)
 			return host_total_vfs;
 	}

 done:
 	return pci_sriov_get_totalvfs(dev->pdev);
 }

 int mlx5_sriov_init(struct mlx5_core_dev *dev)
 {
 	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
 	struct pci_dev *pdev = dev->pdev;
 	int total_vfs, i;

 	if (!mlx5_core_is_pf(dev))
 		return 0;

 	total_vfs = pci_sriov_get_totalvfs(pdev);
 	sriov->max_vfs = mlx5_get_max_vfs(dev);
 	sriov->num_vfs = pci_num_vf(pdev);
 	sriov->vfs_ctx = kcalloc(total_vfs, sizeof(*sriov->vfs_ctx), GFP_KERNEL);
 	if (!sriov->vfs_ctx)
 		return -ENOMEM;

 	for (i = 0; i < total_vfs; i++)
 		BLOCKING_INIT_NOTIFIER_HEAD(&sriov->vfs_ctx[i].notifier);

 	return 0;
 }

 void mlx5_sriov_cleanup(struct mlx5_core_dev *dev)
 {
 	struct mlx5_core_sriov *sriov = &dev->priv.sriov;

 	if (!mlx5_core_is_pf(dev))
 		return;

 	kfree(sriov->vfs_ctx);
 }

 /**
  * mlx5_sriov_blocking_notifier_unregister - Unregister a VF from
  * a notification block chain.
  *
  * @mdev: The mlx5 core device.
  * @vf_id: The VF id.
  * @nb: The notifier block to be unregistered.
  */
 void mlx5_sriov_blocking_notifier_unregister(struct mlx5_core_dev *mdev,
 					     int vf_id,
 					     struct notifier_block *nb)
 {
 	struct mlx5_vf_context *vfs_ctx;
 	struct mlx5_core_sriov *sriov;

 	sriov = &mdev->priv.sriov;
 	if (WARN_ON(vf_id < 0 || vf_id >= sriov->num_vfs))
 		return;

 	vfs_ctx = &sriov->vfs_ctx[vf_id];
 	blocking_notifier_chain_unregister(&vfs_ctx->notifier, nb);
 }
 EXPORT_SYMBOL(mlx5_sriov_blocking_notifier_unregister);

 /**
  * mlx5_sriov_blocking_notifier_register - Register a VF notification
  * block chain.
  *
  * @mdev: The mlx5 core device.
  * @vf_id: The VF id.
  * @nb: The notifier block to be called upon the VF events.
  *
  * Returns 0 on success or an error code.
  */
 int mlx5_sriov_blocking_notifier_register(struct mlx5_core_dev *mdev,
 					  int vf_id,
 					  struct notifier_block *nb)
 {
 	struct mlx5_vf_context *vfs_ctx;
 	struct mlx5_core_sriov *sriov;

 	sriov = &mdev->priv.sriov;
 	if (vf_id < 0 || vf_id >= sriov->num_vfs)
 		return -EINVAL;

 	vfs_ctx = &sriov->vfs_ctx[vf_id];
 	return blocking_notifier_chain_register(&vfs_ctx->notifier, nb);
 }
 EXPORT_SYMBOL(mlx5_sriov_blocking_notifier_register);
	/*
	* Copyright (c) 2014, Mellanox Technologies inc. All rights reserved.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* OpenIB.org BSD license below:
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above
	* copyright notice, this list of conditions and the following
	* disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials
	* provided with the distribution.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include <linux/pci.h>
	#include <linux/mlx5/driver.h>
	#include <linux/mlx5/vport.h>
	#include "mlx5_core.h"
	#include "mlx5_irq.h"
	#include "eswitch.h"

	static int sriov_restore_guids(struct mlx5_core_dev *dev, int vf)
	{
	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
	struct mlx5_hca_vport_context *in;
	int err = 0;

	/* Restore sriov guid and policy settings */
	if (sriov->vfs_ctx[vf].node_guid \|\|
	sriov->vfs_ctx[vf].port_guid \|\|
	sriov->vfs_ctx[vf].policy != MLX5_POLICY_INVALID) {
	in = kzalloc(sizeof(*in), GFP_KERNEL);
	if (!in)
	return -ENOMEM;

	in->node_guid = sriov->vfs_ctx[vf].node_guid;
	in->port_guid = sriov->vfs_ctx[vf].port_guid;
	in->policy = sriov->vfs_ctx[vf].policy;
	in->field_select =
	!!(in->port_guid) * MLX5_HCA_VPORT_SEL_PORT_GUID \|
	!!(in->node_guid) * MLX5_HCA_VPORT_SEL_NODE_GUID \|
	!!(in->policy) * MLX5_HCA_VPORT_SEL_STATE_POLICY;

	err = mlx5_core_modify_hca_vport_context(dev, 1, 1, vf + 1, in);
	if (err)
	mlx5_core_warn(dev, "modify vport context failed, unable to restore VF %d settings\n", vf);

	kfree(in);
	}

	return err;
	}

	static int mlx5_device_enable_sriov(struct mlx5_core_dev *dev, int num_vfs)
	{
	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
	int err, vf, num_msix_count;

	if (!MLX5_ESWITCH_MANAGER(dev))
	goto enable_vfs_hca;

	err = mlx5_eswitch_enable(dev->priv.eswitch, num_vfs);
	if (err) {
	mlx5_core_warn(dev,
	"failed to enable eswitch SRIOV (%d)\n", err);
	return err;
	}

	enable_vfs_hca:
	num_msix_count = mlx5_get_default_msix_vec_count(dev, num_vfs);
	for (vf = 0; vf < num_vfs; vf++) {
	/* Notify the VF before its enablement to let it set
	* some stuff.
	*/
	blocking_notifier_call_chain(&sriov->vfs_ctx[vf].notifier,
	MLX5_PF_NOTIFY_ENABLE_VF, dev);
	err = mlx5_core_enable_hca(dev, vf + 1);
	if (err) {
	mlx5_core_warn(dev, "failed to enable VF %d (%d)\n", vf, err);
	continue;
	}

	err = mlx5_set_msix_vec_count(dev, vf + 1, num_msix_count);
	if (err) {
	mlx5_core_warn(dev,
	"failed to set MSI-X vector counts VF %d, err %d\n",
	vf, err);
	continue;
	}

	sriov->vfs_ctx[vf].enabled = 1;
	if (MLX5_CAP_GEN(dev, port_type) == MLX5_CAP_PORT_TYPE_IB) {
	err = sriov_restore_guids(dev, vf);
	if (err) {
	mlx5_core_warn(dev,
	"failed to restore VF %d settings, err %d\n",
	vf, err);
	continue;
	}
	}
	mlx5_core_dbg(dev, "successfully enabled VF* %d\n", vf);
	}

	return 0;
	}

	static void
	mlx5_device_disable_sriov(struct mlx5_core_dev *dev, int num_vfs, bool clear_vf)
	{
	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
	int err;
	int vf;

	for (vf = num_vfs - 1; vf >= 0; vf--) {
	if (!sriov->vfs_ctx[vf].enabled)
	continue;
	/* Notify the VF before its disablement to let it clean
	* some resources.
	*/
	blocking_notifier_call_chain(&sriov->vfs_ctx[vf].notifier,
	MLX5_PF_NOTIFY_DISABLE_VF, dev);
	err = mlx5_core_disable_hca(dev, vf + 1);
	if (err) {
	mlx5_core_warn(dev, "failed to disable VF %d\n", vf);
	continue;
	}
	sriov->vfs_ctx[vf].enabled = 0;
	}

	mlx5_eswitch_disable_sriov(dev->priv.eswitch, clear_vf);

	if (mlx5_wait_for_pages(dev, &dev->priv.vfs_pages))
	mlx5_core_warn(dev, "timeout reclaiming VFs pages\n");
	}

	static int mlx5_sriov_enable(struct pci_dev *pdev, int num_vfs)
	{
	struct mlx5_core_dev *dev = pci_get_drvdata(pdev);
	struct devlink *devlink = priv_to_devlink(dev);
	int err;

	devl_lock(devlink);
	err = mlx5_device_enable_sriov(dev, num_vfs);
	devl_unlock(devlink);
	if (err) {
	mlx5_core_warn(dev, "mlx5_device_enable_sriov failed : %d\n", err);
	return err;
	}

	err = pci_enable_sriov(pdev, num_vfs);
	if (err) {
	mlx5_core_warn(dev, "pci_enable_sriov failed : %d\n", err);
	mlx5_device_disable_sriov(dev, num_vfs, true);
	}
	return err;
	}

	void mlx5_sriov_disable(struct pci_dev *pdev)
	{
	struct mlx5_core_dev *dev = pci_get_drvdata(pdev);
	struct devlink *devlink = priv_to_devlink(dev);
	int num_vfs = pci_num_vf(dev->pdev);

	pci_disable_sriov(pdev);
	devl_lock(devlink);
	mlx5_device_disable_sriov(dev, num_vfs, true);
	devl_unlock(devlink);
	}

	int mlx5_core_sriov_configure(struct pci_dev *pdev, int num_vfs)
	{
	struct mlx5_core_dev *dev = pci_get_drvdata(pdev);
	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
	int err = 0;

	mlx5_core_dbg(dev, "requested num_vfs %d\n", num_vfs);

	if (num_vfs)
	err = mlx5_sriov_enable(pdev, num_vfs);
	else
	mlx5_sriov_disable(pdev);

	if (!err)
	sriov->num_vfs = num_vfs;
	return err ? err : num_vfs;
	}

	int mlx5_core_sriov_set_msix_vec_count(struct pci_dev *vf, int msix_vec_count)
	{
	struct pci_dev *pf = pci_physfn(vf);
	struct mlx5_core_sriov *sriov;
	struct mlx5_core_dev *dev;
	int num_vf_msix, id;

	dev = pci_get_drvdata(pf);
	num_vf_msix = MLX5_CAP_GEN_MAX(dev, num_total_dynamic_vf_msix);
	if (!num_vf_msix)
	return -EOPNOTSUPP;

	if (!msix_vec_count)
	msix_vec_count =
	mlx5_get_default_msix_vec_count(dev, pci_num_vf(pf));

	sriov = &dev->priv.sriov;
	id = pci_iov_vf_id(vf);
	if (id < 0 \|\| !sriov->vfs_ctx[id].enabled)
	return -EINVAL;

	return mlx5_set_msix_vec_count(dev, id + 1, msix_vec_count);
	}

	int mlx5_sriov_attach(struct mlx5_core_dev *dev)
	{
	if (!mlx5_core_is_pf(dev) \|\| !pci_num_vf(dev->pdev))
	return 0;

	/* If sriov VFs exist in PCI level, enable them in device level */
	return mlx5_device_enable_sriov(dev, pci_num_vf(dev->pdev));
	}

	void mlx5_sriov_detach(struct mlx5_core_dev *dev)
	{
	if (!mlx5_core_is_pf(dev))
	return;

	mlx5_device_disable_sriov(dev, pci_num_vf(dev->pdev), false);
	}

	static u16 mlx5_get_max_vfs(struct mlx5_core_dev *dev)
	{
	u16 host_total_vfs;
	const u32 *out;

	if (mlx5_core_is_ecpf_esw_manager(dev)) {
	out = mlx5_esw_query_functions(dev);

	/* Old FW doesn't support getting total_vfs from esw func
	* but supports getting it from pci_sriov.
	*/
	if (IS_ERR(out))
	goto done;
	host_total_vfs = MLX5_GET(query_esw_functions_out, out,
	host_params_context.host_total_vfs);
	kvfree(out);
	if (host_total_vfs)
	return host_total_vfs;
	}

	done:
	return pci_sriov_get_totalvfs(dev->pdev);
	}

	int mlx5_sriov_init(struct mlx5_core_dev *dev)
	{
	struct mlx5_core_sriov *sriov = &dev->priv.sriov;
	struct pci_dev *pdev = dev->pdev;
	int total_vfs, i;

	if (!mlx5_core_is_pf(dev))
	return 0;

	total_vfs = pci_sriov_get_totalvfs(pdev);
	sriov->max_vfs = mlx5_get_max_vfs(dev);
	sriov->num_vfs = pci_num_vf(pdev);
	sriov->vfs_ctx = kcalloc(total_vfs, sizeof(*sriov->vfs_ctx), GFP_KERNEL);
	if (!sriov->vfs_ctx)
	return -ENOMEM;

	for (i = 0; i < total_vfs; i++)
	BLOCKING_INIT_NOTIFIER_HEAD(&sriov->vfs_ctx[i].notifier);

	return 0;
	}

	void mlx5_sriov_cleanup(struct mlx5_core_dev *dev)
	{
	struct mlx5_core_sriov *sriov = &dev->priv.sriov;

	if (!mlx5_core_is_pf(dev))
	return;

	kfree(sriov->vfs_ctx);
	}

	/**
	* mlx5_sriov_blocking_notifier_unregister - Unregister a VF from
	* a notification block chain.
	*
	* @mdev: The mlx5 core device.
	* @vf_id: The VF id.
	* @nb: The notifier block to be unregistered.
	*/
	void mlx5_sriov_blocking_notifier_unregister(struct mlx5_core_dev *mdev,
	int vf_id,
	struct notifier_block *nb)
	{
	struct mlx5_vf_context *vfs_ctx;
	struct mlx5_core_sriov *sriov;

	sriov = &mdev->priv.sriov;
	if (WARN_ON(vf_id < 0 \|\| vf_id >= sriov->num_vfs))
	return;

	vfs_ctx = &sriov->vfs_ctx[vf_id];
	blocking_notifier_chain_unregister(&vfs_ctx->notifier, nb);
	}
	EXPORT_SYMBOL(mlx5_sriov_blocking_notifier_unregister);

	/**
	* mlx5_sriov_blocking_notifier_register - Register a VF notification
	* block chain.
	*
	* @mdev: The mlx5 core device.
	* @vf_id: The VF id.
	* @nb: The notifier block to be called upon the VF events.
	*
	* Returns 0 on success or an error code.
	*/
	int mlx5_sriov_blocking_notifier_register(struct mlx5_core_dev *mdev,
	int vf_id,
	struct notifier_block *nb)
	{
	struct mlx5_vf_context *vfs_ctx;
	struct mlx5_core_sriov *sriov;

	sriov = &mdev->priv.sriov;
	if (vf_id < 0 \|\| vf_id >= sriov->num_vfs)
	return -EINVAL;

	vfs_ctx = &sriov->vfs_ctx[vf_id];
	return blocking_notifier_chain_register(&vfs_ctx->notifier, nb);
	}
	EXPORT_SYMBOL(mlx5_sriov_blocking_notifier_register);