Re: [PATCH RFC v3 09/14] dmaengine: idxd: add configuration component of driver

[Vinod Koul]

On 17-12-19, 16:33, Dave Jiang wrote:
> The device is left unconfigured when the driver is loaded. Various
> components are configured via the driver sysfs attributes. Once

can you document what attributes are configured this way and why should
userspace configure this?

> configuration is done, the device can be enabled by writing the device name
> to the bind attribute of the device driver sysfs. Disabling can be done
> similarly. Also the individual work queues can also be enabled and disabled
> through the bind/unbind attributes. A constructed hierarchy is created
> through the struct device framework in order to provide appropriate
> configuration points and device state and status. This hierarchy is
> presented off the virtual DSA bus.
> 
> i.e. /sys/bus/dsa/...
> 
> 
> Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> ---
>  drivers/dma/idxd/Makefile    |    2 
>  drivers/dma/idxd/device.c    |   25 +
>  drivers/dma/idxd/idxd.h      |   25 +
>  drivers/dma/idxd/init.c      |   27 +
>  drivers/dma/idxd/registers.h |    1 
>  drivers/dma/idxd/sysfs.c     | 1452 ++++++++++++++++++++++++++++++++++++++++++

And we need these added to ABI document as well, please add that

>  6 files changed, 1530 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/dma/idxd/sysfs.c
> 
> diff --git a/drivers/dma/idxd/Makefile b/drivers/dma/idxd/Makefile
> index 0dd1ca77513f..a552560a03dc 100644
> --- a/drivers/dma/idxd/Makefile
> +++ b/drivers/dma/idxd/Makefile
> @@ -1,2 +1,2 @@
>  obj-$(CONFIG_INTEL_IDXD) += idxd.o
> -idxd-y := init.o irq.o device.o
> +idxd-y := init.o irq.o device.o sysfs.o
> diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c
> index 88739c11e163..74a60a8bef76 100644
> --- a/drivers/dma/idxd/device.c
> +++ b/drivers/dma/idxd/device.c
> @@ -292,6 +292,31 @@ int idxd_wq_disable(struct idxd_wq *wq)
>  	return 0;
>  }
>  
> +int idxd_wq_map_portal(struct idxd_wq *wq)
> +{
> +	struct idxd_device *idxd = wq->idxd;
> +	struct pci_dev *pdev = idxd->pdev;
> +	struct device *dev = &pdev->dev;
> +	resource_size_t start;
> +
> +	start = pci_resource_start(pdev, IDXD_WQ_BAR);
> +	start = start + wq->id * IDXD_PORTAL_SIZE;
> +
> +	wq->dportal = devm_ioremap(dev, start, IDXD_PORTAL_SIZE);
> +	if (!wq->dportal)
> +		return -ENOMEM;
> +	dev_dbg(dev, "wq %d portal mapped at %p\n", wq->id, wq->dportal);
> +
> +	return 0;
> +}
> +
> +void idxd_wq_unmap_portal(struct idxd_wq *wq)
> +{
> +	struct device *dev = &wq->idxd->pdev->dev;
> +
> +	devm_iounmap(dev, wq->dportal);
> +}
> +
>  /* Device control bits */
>  static inline bool idxd_is_enabled(struct idxd_device *idxd)
>  {
> diff --git a/drivers/dma/idxd/idxd.h b/drivers/dma/idxd/idxd.h
> index 039a3cb84214..076456357962 100644
> --- a/drivers/dma/idxd/idxd.h
> +++ b/drivers/dma/idxd/idxd.h
> @@ -161,6 +161,7 @@ struct idxd_device {
>  	int max_wqs;
>  	int max_wq_size;
>  	int token_limit;
> +	int nr_tokens;		/* non-reserved tokens */
>  
>  	union sw_err_reg sw_err;
>  
> @@ -201,7 +202,28 @@ static inline void idxd_set_type(struct idxd_device *idxd)
>  		idxd->type = IDXD_TYPE_UNKNOWN;
>  }
>  
> +static inline void idxd_wq_get(struct idxd_wq *wq)
> +{
> +	wq->client_count++;
> +}
> +
> +static inline void idxd_wq_put(struct idxd_wq *wq)
> +{
> +	wq->client_count--;
> +}
> +
> +static inline int idxd_wq_refcount(struct idxd_wq *wq)
> +{
> +	return wq->client_count;
> +};
> +
>  const char *idxd_get_dev_name(struct idxd_device *idxd);
> +int idxd_register_bus_type(void);
> +void idxd_unregister_bus_type(void);
> +int idxd_setup_sysfs(struct idxd_device *idxd);
> +void idxd_cleanup_sysfs(struct idxd_device *idxd);
> +int idxd_register_driver(void);
> +void idxd_unregister_driver(void);
>  
>  /* device interrupt control */
>  irqreturn_t idxd_irq_handler(int vec, void *data);
> @@ -223,9 +245,12 @@ int idxd_device_config(struct idxd_device *idxd);
>  void idxd_device_wqs_clear_state(struct idxd_device *idxd);
>  
>  /* work queue control */
> +void idxd_free_desc(struct idxd_wq *wq, struct idxd_desc *desc);
>  int idxd_wq_alloc_resources(struct idxd_wq *wq);
>  void idxd_wq_free_resources(struct idxd_wq *wq);
>  int idxd_wq_enable(struct idxd_wq *wq);
>  int idxd_wq_disable(struct idxd_wq *wq);
> +int idxd_wq_map_portal(struct idxd_wq *wq);
> +void idxd_wq_unmap_portal(struct idxd_wq *wq);
>  
>  #endif
> diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
> index 6e89a87d62b0..229386464923 100644
> --- a/drivers/dma/idxd/init.c
> +++ b/drivers/dma/idxd/init.c
> @@ -244,6 +244,7 @@ static void idxd_read_caps(struct idxd_device *idxd)
>  	dev_dbg(dev, "max groups: %u\n", idxd->max_groups);
>  	idxd->max_tokens = idxd->hw.group_cap.total_tokens;
>  	dev_dbg(dev, "max tokens: %u\n", idxd->max_tokens);
> +	idxd->nr_tokens = idxd->max_tokens;
>  
>  	/* read engine capabilities */
>  	idxd->hw.engine_cap.bits =
> @@ -381,6 +382,14 @@ static int idxd_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
>  		return -ENODEV;
>  	}
>  
> +	rc = idxd_setup_sysfs(idxd);
> +	if (rc) {
> +		dev_err(dev, "IDXD sysfs setup failed\n");
> +		return -ENODEV;
> +	}
> +
> +	idxd->state = IDXD_DEV_CONF_READY;
> +
>  	dev_info(&pdev->dev, "Intel(R) Accelerator Device (v%x)\n",
>  		 idxd->hw.version);
>  
> @@ -418,6 +427,7 @@ static void idxd_remove(struct pci_dev *pdev)
>  	struct idxd_device *idxd = pci_get_drvdata(pdev);
>  
>  	dev_dbg(&pdev->dev, "%s called\n", __func__);
> +	idxd_cleanup_sysfs(idxd);
>  	idxd_shutdown(pdev);
>  	idxd_wqs_free_lock(idxd);
>  	mutex_lock(&idxd_idr_lock);
> @@ -453,16 +463,31 @@ static int __init idxd_init_module(void)
>  	for (i = 0; i < IDXD_TYPE_MAX; i++)
>  		idr_init(&idxd_idrs[i]);
>  
> +	err = idxd_register_bus_type();
> +	if (err < 0)
> +		return err;
> +
> +	err = idxd_register_driver();
> +	if (err < 0)
> +		goto err_idxd_driver_register;
> +
>  	err = pci_register_driver(&idxd_pci_driver);
>  	if (err)
> -		return err;
> +		goto err_pci_register;
>  
>  	return 0;
> +
> +err_pci_register:
> +	idxd_unregister_driver();
> +err_idxd_driver_register:
> +	idxd_unregister_bus_type();
> +	return err;
>  }
>  module_init(idxd_init_module);
>  
>  static void __exit idxd_exit_module(void)
>  {
>  	pci_unregister_driver(&idxd_pci_driver);
> +	idxd_unregister_bus_type();
>  }
>  module_exit(idxd_exit_module);
> diff --git a/drivers/dma/idxd/registers.h b/drivers/dma/idxd/registers.h
> index 77275a07fa61..b81b4c8d6f58 100644
> --- a/drivers/dma/idxd/registers.h
> +++ b/drivers/dma/idxd/registers.h
> @@ -8,6 +8,7 @@
>  
>  #define IDXD_MMIO_BAR		0
>  #define IDXD_WQ_BAR		2
> +#define IDXD_PORTAL_SIZE	0x4000
>  
>  /* MMIO Device BAR0 Registers */
>  #define IDXD_VER_OFFSET			0x00
> diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
> new file mode 100644
> index 000000000000..b6da47b52116
> --- /dev/null
> +++ b/drivers/dma/idxd/sysfs.c
> @@ -0,0 +1,1452 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright(c) 2019 Intel Corporation. All rights rsvd. */
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/device.h>
> +#include <linux/io-64-nonatomic-lo-hi.h>
> +#include <uapi/linux/idxd.h>
> +#include "registers.h"
> +#include "idxd.h"
> +
> +static char *idxd_wq_type_names[] = {
> +	[IDXD_WQT_NONE]		= "none",
> +	[IDXD_WQT_KERNEL]	= "kernel",
> +};
> +
> +static void idxd_conf_device_release(struct device *dev)
> +{
> +	dev_dbg(dev, "%s for %s\n", __func__, dev_name(dev));
> +}
> +
> +static struct device_type idxd_group_device_type = {
> +	.name = "group",
> +	.release = idxd_conf_device_release,
> +};
> +
> +static struct device_type idxd_wq_device_type = {
> +	.name = "wq",
> +	.release = idxd_conf_device_release,
> +};
> +
> +static struct device_type idxd_engine_device_type = {
> +	.name = "engine",
> +	.release = idxd_conf_device_release,
> +};
> +
> +static struct device_type dsa_device_type = {
> +	.name = "dsa",
> +	.release = idxd_conf_device_release,
> +};
> +
> +static inline bool is_dsa_dev(struct device *dev)
> +{
> +	return dev ? dev->type == &dsa_device_type : false;
> +}
> +
> +static inline bool is_idxd_dev(struct device *dev)
> +{
> +	return is_dsa_dev(dev);
> +}
> +
> +static inline bool is_idxd_wq_dev(struct device *dev)
> +{
> +	return dev ? dev->type == &idxd_wq_device_type : false;
> +}
> +
> +static int idxd_config_bus_match(struct device *dev,
> +				 struct device_driver *drv)
> +{
> +	int matched = 0;
> +
> +	if (is_idxd_dev(dev)) {
> +		struct idxd_device *idxd = confdev_to_idxd(dev);
> +
> +		if (idxd->state != IDXD_DEV_CONF_READY)
> +			return 0;
> +		matched = 1;
> +	} else if (is_idxd_wq_dev(dev)) {
> +		struct idxd_wq *wq = confdev_to_wq(dev);
> +		struct idxd_device *idxd = wq->idxd;
> +
> +		if (idxd->state < IDXD_DEV_CONF_READY)
> +			return 0;
> +
> +		if (wq->state != IDXD_WQ_DISABLED) {
> +			dev_dbg(dev, "%s not disabled\n", dev_name(dev));
> +			return 0;
> +		}
> +		matched = 1;
> +	}
> +
> +	if (matched)
> +		dev_dbg(dev, "%s matched\n", dev_name(dev));
> +
> +	return matched;
> +}
> +
> +static int idxd_config_bus_probe(struct device *dev)
> +{
> +	int rc;
> +	unsigned long flags;
> +
> +	dev_dbg(dev, "%s called\n", __func__);
> +
> +	if (is_idxd_dev(dev)) {
> +		struct idxd_device *idxd = confdev_to_idxd(dev);
> +
> +		if (idxd->state != IDXD_DEV_CONF_READY) {
> +			dev_warn(dev, "Device not ready for config\n");
> +			return -EBUSY;
> +		}
> +
> +		spin_lock_irqsave(&idxd->dev_lock, flags);
> +
> +		/* Perform IDXD configuration and enabling */
> +		rc = idxd_device_config(idxd);
> +		if (rc < 0) {
> +			spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +			dev_warn(dev, "Device config failed: %d\n", rc);
> +			return rc;
> +		}
> +
> +		/* start device */
> +		rc = idxd_device_enable(idxd);
> +		if (rc < 0) {
> +			spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +			dev_warn(dev, "Device enable failed: %d\n", rc);
> +			return rc;
> +		}
> +
> +		spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +		dev_info(dev, "Device %s enabled\n", dev_name(dev));
> +
> +		return 0;
> +	} else if (is_idxd_wq_dev(dev)) {
> +		struct idxd_wq *wq = confdev_to_wq(dev);
> +		struct idxd_device *idxd = wq->idxd;
> +
> +		mutex_lock(&wq->wq_lock);
> +
> +		if (idxd->state != IDXD_DEV_ENABLED) {
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "Enabling while device not enabled.\n");
> +			return -EPERM;
> +		}
> +
> +		if (wq->state != IDXD_WQ_DISABLED) {
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "WQ %d already enabled.\n", wq->id);
> +			return -EBUSY;
> +		}
> +
> +		if (!wq->group) {
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "WQ not attached to group.\n");
> +			return -EINVAL;
> +		}
> +
> +		if (strlen(wq->name) == 0) {
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "WQ name not set.\n");
> +			return -EINVAL;
> +		}
> +
> +		rc = idxd_wq_alloc_resources(wq);
> +		if (rc < 0) {
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "WQ resource allocation failed\n");
> +			return rc;
> +		}
> +
> +		spin_lock_irqsave(&idxd->dev_lock, flags);
> +		rc = idxd_device_config(idxd);
> +		if (rc < 0) {
> +			spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "Writing WQ %d config failed: %d\n",
> +				 wq->id, rc);
> +			return rc;
> +		}
> +
> +		rc = idxd_wq_enable(wq);
> +		if (rc < 0) {
> +			spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +			mutex_unlock(&wq->wq_lock);
> +			dev_warn(dev, "WQ %d enabling failed: %d\n",
> +				 wq->id, rc);
> +			return rc;
> +		}
> +		spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +
> +		rc = idxd_wq_map_portal(wq);
> +		if (rc < 0) {
> +			dev_warn(dev, "wq portal mapping failed: %d\n", rc);
> +			rc = idxd_wq_disable(wq);
> +			if (rc < 0)
> +				dev_warn(dev, "IDXD wq disable failed\n");
> +			spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +			mutex_unlock(&wq->wq_lock);
> +			return rc;
> +		}
> +
> +		wq->client_count = 0;
> +
> +		dev_info(dev, "wq %s enabled\n", dev_name(&wq->conf_dev));
> +		mutex_unlock(&wq->wq_lock);
> +		return 0;
> +	}
> +
> +	return -ENODEV;
> +}
> +
> +static void disable_wq(struct idxd_wq *wq)
> +{
> +	struct idxd_device *idxd = wq->idxd;
> +	struct device *dev = &idxd->pdev->dev;
> +	unsigned long flags;
> +	int rc;
> +
> +	mutex_lock(&wq->wq_lock);
> +	dev_dbg(dev, "%s removing WQ %s\n", __func__, dev_name(&wq->conf_dev));
> +	if (wq->state == IDXD_WQ_DISABLED) {
> +		mutex_unlock(&wq->wq_lock);
> +		return;
> +	}
> +
> +	if (idxd_wq_refcount(wq))
> +		dev_warn(dev, "Clients has claim on wq %d: %d\n",
> +			 wq->id, idxd_wq_refcount(wq));
> +
> +	idxd_wq_unmap_portal(wq);
> +
> +	spin_lock_irqsave(&idxd->dev_lock, flags);
> +	rc = idxd_wq_disable(wq);
> +	spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +
> +	idxd_wq_free_resources(wq);
> +	wq->client_count = 0;
> +	mutex_unlock(&wq->wq_lock);
> +
> +	if (rc < 0)
> +		dev_warn(dev, "Failed to disable %s: %d\n",
> +			 dev_name(&wq->conf_dev), rc);
> +	else
> +		dev_info(dev, "wq %s disabled\n", dev_name(&wq->conf_dev));
> +}
> +
> +static int idxd_config_bus_remove(struct device *dev)
> +{
> +	int rc;
> +	unsigned long flags;
> +
> +	dev_dbg(dev, "%s called for %s\n", __func__, dev_name(dev));
> +
> +	/* disable workqueue here */
> +	if (is_idxd_wq_dev(dev)) {
> +		struct idxd_wq *wq = confdev_to_wq(dev);
> +
> +		disable_wq(wq);
> +	} else if (is_idxd_dev(dev)) {
> +		struct idxd_device *idxd = confdev_to_idxd(dev);
> +		int i;
> +
> +		dev_dbg(dev, "%s removing dev %s\n", __func__,
> +			dev_name(&idxd->conf_dev));
> +		for (i = 0; i < idxd->max_wqs; i++) {
> +			struct idxd_wq *wq = &idxd->wqs[i];
> +
> +			if (wq->state == IDXD_WQ_DISABLED)
> +				continue;
> +			dev_warn(dev, "Active wq %d on disable %s.\n", i,
> +				 dev_name(&idxd->conf_dev));
> +			device_release_driver(&wq->conf_dev);
> +		}
> +
> +		spin_lock_irqsave(&idxd->dev_lock, flags);
> +		rc = idxd_device_disable(idxd);
> +		spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +		if (rc < 0)
> +			dev_warn(dev, "Device disable failed\n");
> +		else
> +			dev_info(dev, "Device %s disabled\n", dev_name(dev));
> +	}
> +
> +	return 0;
> +}
> +
> +static void idxd_config_bus_shutdown(struct device *dev)
> +{
> +	dev_dbg(dev, "%s called\n", __func__);
> +}
> +
> +static struct bus_type dsa_bus_type = {
> +	.name = "dsa",
> +	.match = idxd_config_bus_match,
> +	.probe = idxd_config_bus_probe,
> +	.remove = idxd_config_bus_remove,
> +	.shutdown = idxd_config_bus_shutdown,
> +};
> +
> +static struct bus_type *idxd_bus_types[] = {
> +	&dsa_bus_type
> +};
> +
> +static struct idxd_device_driver dsa_drv = {
> +	.drv = {
> +		.name = "dsa",
> +		.bus = &dsa_bus_type,
> +		.owner = THIS_MODULE,
> +		.mod_name = KBUILD_MODNAME,
> +	},
> +};
> +
> +static struct idxd_device_driver *idxd_drvs[] = {
> +	&dsa_drv
> +};
> +
> +static struct bus_type *idxd_get_bus_type(struct idxd_device *idxd)
> +{
> +	return idxd_bus_types[idxd->type];
> +}
> +
> +static struct device_type *idxd_get_device_type(struct idxd_device *idxd)
> +{
> +	if (idxd->type == IDXD_TYPE_DSA)
> +		return &dsa_device_type;
> +	else
> +		return NULL;
> +}
> +
> +/* IDXD generic driver setup */
> +int idxd_register_driver(void)
> +{
> +	int i, rc;
> +
> +	for (i = 0; i < IDXD_TYPE_MAX; i++) {
> +		rc = driver_register(&idxd_drvs[i]->drv);
> +		if (rc < 0)
> +			goto drv_fail;
> +	}
> +
> +	return 0;
> +
> +drv_fail:
> +	for (; i > 0; i--)
> +		driver_unregister(&idxd_drvs[i]->drv);
> +	return rc;
> +}
> +
> +void idxd_unregister_driver(void)
> +{
> +	int i;
> +
> +	for (i = 0; i < IDXD_TYPE_MAX; i++)
> +		driver_unregister(&idxd_drvs[i]->drv);
> +}
> +
> +/* IDXD engine attributes */
> +static ssize_t engine_group_id_show(struct device *dev,
> +				    struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_engine *engine =
> +		container_of(dev, struct idxd_engine, conf_dev);
> +
> +	if (engine->group)
> +		return sprintf(buf, "%d\n", engine->group->id);
> +	else
> +		return sprintf(buf, "%d\n", -1);
> +}
> +
> +static ssize_t engine_group_id_store(struct device *dev,
> +				     struct device_attribute *attr,
> +				     const char *buf, size_t count)
> +{
> +	struct idxd_engine *engine =
> +		container_of(dev, struct idxd_engine, conf_dev);
> +	struct idxd_device *idxd = engine->idxd;
> +	long id;
> +	int rc;
> +	struct idxd_group *prevg, *group;
> +
> +	rc = kstrtol(buf, 10, &id);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (id > idxd->max_groups - 1 || id < -1)
> +		return -EINVAL;
> +
> +	if (id == -1) {
> +		if (engine->group) {
> +			engine->group->num_engines--;
> +			engine->group = NULL;
> +		}
> +		return count;
> +	}
> +
> +	group = &idxd->groups[id];
> +	prevg = engine->group;
> +
> +	if (prevg)
> +		prevg->num_engines--;
> +	engine->group = &idxd->groups[id];
> +	engine->group->num_engines++;
> +
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_engine_group =
> +		__ATTR(group_id, 0644, engine_group_id_show,
> +		       engine_group_id_store);
> +
> +static struct attribute *idxd_engine_attributes[] = {
> +	&dev_attr_engine_group.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group idxd_engine_attribute_group = {
> +	.attrs = idxd_engine_attributes,
> +};
> +
> +static const struct attribute_group *idxd_engine_attribute_groups[] = {
> +	&idxd_engine_attribute_group,
> +	NULL,
> +};
> +
> +/* Group attributes */
> +
> +static void idxd_set_free_tokens(struct idxd_device *idxd)
> +{
> +	int i, tokens;
> +
> +	for (i = 0, tokens = 0; i < idxd->max_groups; i++) {
> +		struct idxd_group *g = &idxd->groups[i];
> +
> +		tokens += g->tokens_reserved;
> +	}
> +
> +	idxd->nr_tokens = idxd->max_tokens - tokens;
> +}
> +
> +static ssize_t group_tokens_reserved_show(struct device *dev,
> +					  struct device_attribute *attr,
> +					  char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +
> +	return sprintf(buf, "%u\n", group->tokens_reserved);
> +}
> +
> +static ssize_t group_tokens_reserved_store(struct device *dev,
> +					   struct device_attribute *attr,
> +					   const char *buf, size_t count)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	struct idxd_device *idxd = group->idxd;
> +	unsigned long val;
> +	int rc;
> +
> +	rc = kstrtoul(buf, 10, &val);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (idxd->state == IDXD_DEV_ENABLED)
> +		return -EPERM;
> +
> +	if (idxd->token_limit == 0)
> +		return -EPERM;
> +
> +	if (val > idxd->max_tokens)
> +		return -EINVAL;
> +
> +	if (val > idxd->nr_tokens)
> +		return -EINVAL;
> +
> +	group->tokens_reserved = val;
> +	idxd_set_free_tokens(idxd);
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_group_tokens_reserved =
> +		__ATTR(tokens_reserved, 0644, group_tokens_reserved_show,
> +		       group_tokens_reserved_store);
> +
> +static ssize_t group_tokens_allowed_show(struct device *dev,
> +					 struct device_attribute *attr,
> +					 char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +
> +	return sprintf(buf, "%u\n", group->tokens_allowed);
> +}
> +
> +static ssize_t group_tokens_allowed_store(struct device *dev,
> +					  struct device_attribute *attr,
> +					  const char *buf, size_t count)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	struct idxd_device *idxd = group->idxd;
> +	unsigned long val;
> +	int rc;
> +
> +	rc = kstrtoul(buf, 10, &val);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (idxd->state == IDXD_DEV_ENABLED)
> +		return -EPERM;
> +
> +	if (idxd->token_limit == 0)
> +		return -EPERM;
> +	if (val < 4 * group->num_engines ||
> +	    val > group->tokens_reserved + idxd->nr_tokens)
> +		return -EINVAL;
> +
> +	group->tokens_allowed = val;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_group_tokens_allowed =
> +		__ATTR(tokens_allowed, 0644, group_tokens_allowed_show,
> +		       group_tokens_allowed_store);
> +
> +static ssize_t group_use_token_limit_show(struct device *dev,
> +					  struct device_attribute *attr,
> +					  char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +
> +	return sprintf(buf, "%u\n", group->use_token_limit);
> +}
> +
> +static ssize_t group_use_token_limit_store(struct device *dev,
> +					   struct device_attribute *attr,
> +					   const char *buf, size_t count)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	struct idxd_device *idxd = group->idxd;
> +	unsigned long val;
> +	int rc;
> +
> +	rc = kstrtoul(buf, 10, &val);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (idxd->state == IDXD_DEV_ENABLED)
> +		return -EPERM;
> +
> +	if (idxd->token_limit == 0)
> +		return -EPERM;
> +
> +	group->use_token_limit = !!val;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_group_use_token_limit =
> +		__ATTR(use_token_limit, 0644, group_use_token_limit_show,
> +		       group_use_token_limit_store);
> +
> +static ssize_t group_engines_show(struct device *dev,
> +				  struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	int i, rc = 0;
> +	char *tmp = buf;
> +	struct idxd_device *idxd = group->idxd;
> +
> +	for (i = 0; i < idxd->max_engines; i++) {
> +		struct idxd_engine *engine = &idxd->engines[i];
> +
> +		if (!engine->group)
> +			continue;
> +
> +		if (engine->group->id == group->id)
> +			rc += sprintf(tmp + rc, "engine%d.%d ",
> +					idxd->id, engine->id);
> +	}
> +
> +	rc--;
> +	rc += sprintf(tmp + rc, "\n");
> +
> +	return rc;
> +}
> +
> +static struct device_attribute dev_attr_group_engines =
> +		__ATTR(engines, 0444, group_engines_show, NULL);
> +
> +static ssize_t group_work_queues_show(struct device *dev,
> +				      struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	int i, rc = 0;
> +	char *tmp = buf;
> +	struct idxd_device *idxd = group->idxd;
> +
> +	for (i = 0; i < idxd->max_wqs; i++) {
> +		struct idxd_wq *wq = &idxd->wqs[i];
> +
> +		if (!wq->group)
> +			continue;
> +
> +		if (wq->group->id == group->id)
> +			rc += sprintf(tmp + rc, "wq%d.%d ",
> +					idxd->id, wq->id);
> +	}
> +
> +	rc--;
> +	rc += sprintf(tmp + rc, "\n");
> +
> +	return rc;
> +}
> +
> +static struct device_attribute dev_attr_group_work_queues =
> +		__ATTR(work_queues, 0444, group_work_queues_show, NULL);
> +
> +static ssize_t group_traffic_class_a_show(struct device *dev,
> +					  struct device_attribute *attr,
> +					  char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +
> +	return sprintf(buf, "%d\n", group->tc_a);
> +}
> +
> +static ssize_t group_traffic_class_a_store(struct device *dev,
> +					   struct device_attribute *attr,
> +					   const char *buf, size_t count)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	struct idxd_device *idxd = group->idxd;
> +	long val;
> +	int rc;
> +
> +	rc = kstrtol(buf, 10, &val);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (idxd->state == IDXD_DEV_ENABLED)
> +		return -EPERM;
> +
> +	if (val < 0 || val > 7)
> +		return -EINVAL;
> +
> +	group->tc_a = val;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_group_traffic_class_a =
> +		__ATTR(traffic_class_a, 0644, group_traffic_class_a_show,
> +		       group_traffic_class_a_store);
> +
> +static ssize_t group_traffic_class_b_show(struct device *dev,
> +					  struct device_attribute *attr,
> +					  char *buf)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +
> +	return sprintf(buf, "%d\n", group->tc_b);
> +}
> +
> +static ssize_t group_traffic_class_b_store(struct device *dev,
> +					   struct device_attribute *attr,
> +					   const char *buf, size_t count)
> +{
> +	struct idxd_group *group =
> +		container_of(dev, struct idxd_group, conf_dev);
> +	struct idxd_device *idxd = group->idxd;
> +	long val;
> +	int rc;
> +
> +	rc = kstrtol(buf, 10, &val);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (idxd->state == IDXD_DEV_ENABLED)
> +		return -EPERM;
> +
> +	if (val < 0 || val > 7)
> +		return -EINVAL;
> +
> +	group->tc_b = val;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_group_traffic_class_b =
> +		__ATTR(traffic_class_b, 0644, group_traffic_class_b_show,
> +		       group_traffic_class_b_store);
> +
> +static struct attribute *idxd_group_attributes[] = {
> +	&dev_attr_group_work_queues.attr,
> +	&dev_attr_group_engines.attr,
> +	&dev_attr_group_use_token_limit.attr,
> +	&dev_attr_group_tokens_allowed.attr,
> +	&dev_attr_group_tokens_reserved.attr,
> +	&dev_attr_group_traffic_class_a.attr,
> +	&dev_attr_group_traffic_class_b.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group idxd_group_attribute_group = {
> +	.attrs = idxd_group_attributes,
> +};
> +
> +static const struct attribute_group *idxd_group_attribute_groups[] = {
> +	&idxd_group_attribute_group,
> +	NULL,
> +};
> +
> +/* IDXD work queue attribs */
> +static ssize_t wq_clients_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	return sprintf(buf, "%d\n", wq->client_count);
> +}
> +
> +static struct device_attribute dev_attr_wq_clients =
> +		__ATTR(clients, 0444, wq_clients_show, NULL);
> +
> +static ssize_t wq_state_show(struct device *dev,
> +			     struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	switch (wq->state) {
> +	case IDXD_WQ_DISABLED:
> +		return sprintf(buf, "disabled\n");
> +	case IDXD_WQ_ENABLED:
> +		return sprintf(buf, "enabled\n");
> +	}
> +
> +	return sprintf(buf, "unknown\n");
> +}
> +
> +static struct device_attribute dev_attr_wq_state =
> +		__ATTR(state, 0444, wq_state_show, NULL);
> +
> +static ssize_t wq_group_id_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	if (wq->group)
> +		return sprintf(buf, "%u\n", wq->group->id);
> +	else
> +		return sprintf(buf, "-1\n");
> +}
> +
> +static ssize_t wq_group_id_store(struct device *dev,
> +				 struct device_attribute *attr,
> +				 const char *buf, size_t count)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +	struct idxd_device *idxd = wq->idxd;
> +	long id;
> +	int rc;
> +	struct idxd_group *prevg, *group;
> +
> +	rc = kstrtol(buf, 10, &id);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (wq->state != IDXD_WQ_DISABLED)
> +		return -EPERM;
> +
> +	if (id > idxd->max_groups - 1 || id < -1)
> +		return -EINVAL;
> +
> +	if (id == -1) {
> +		if (wq->group) {
> +			wq->group->num_wqs--;
> +			wq->group = NULL;
> +		}
> +		return count;
> +	}
> +
> +	group = &idxd->groups[id];
> +	prevg = wq->group;
> +
> +	if (prevg)
> +		prevg->num_wqs--;
> +	wq->group = group;
> +	group->num_wqs++;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_wq_group_id =
> +		__ATTR(group_id, 0644, wq_group_id_show, wq_group_id_store);
> +
> +static ssize_t wq_mode_show(struct device *dev, struct device_attribute *attr,
> +			    char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	return sprintf(buf, "%s\n",
> +			wq_dedicated(wq) ? "dedicated" : "shared");
> +}
> +
> +static ssize_t wq_mode_store(struct device *dev,
> +			     struct device_attribute *attr, const char *buf,
> +			     size_t count)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +	struct idxd_device *idxd = wq->idxd;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (wq->state != IDXD_WQ_DISABLED)
> +		return -EPERM;
> +
> +	if (sysfs_streq(buf, "dedicated")) {
> +		set_bit(WQ_FLAG_DEDICATED, &wq->flags);
> +		wq->threshold = 0;
> +	} else {
> +		return -EINVAL;
> +	}
> +
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_wq_mode =
> +		__ATTR(mode, 0644, wq_mode_show, wq_mode_store);
> +
> +static ssize_t wq_size_show(struct device *dev, struct device_attribute *attr,
> +			    char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	return sprintf(buf, "%u\n", wq->size);
> +}
> +
> +static ssize_t wq_size_store(struct device *dev,
> +			     struct device_attribute *attr, const char *buf,
> +			     size_t count)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +	unsigned long size;
> +	struct idxd_device *idxd = wq->idxd;
> +	int rc;
> +
> +	rc = kstrtoul(buf, 10, &size);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (wq->state != IDXD_WQ_DISABLED)
> +		return -EPERM;
> +
> +	if (size > idxd->max_wq_size)
> +		return -EINVAL;
> +
> +	wq->size = size;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_wq_size =
> +		__ATTR(size, 0644, wq_size_show, wq_size_store);
> +
> +static ssize_t wq_priority_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	return sprintf(buf, "%u\n", wq->priority);
> +}
> +
> +static ssize_t wq_priority_store(struct device *dev,
> +				 struct device_attribute *attr,
> +				 const char *buf, size_t count)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +	unsigned long prio;
> +	struct idxd_device *idxd = wq->idxd;
> +	int rc;
> +
> +	rc = kstrtoul(buf, 10, &prio);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (wq->state != IDXD_WQ_DISABLED)
> +		return -EPERM;
> +
> +	if (prio > IDXD_MAX_PRIORITY)
> +		return -EINVAL;
> +
> +	wq->priority = prio;
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_wq_priority =
> +		__ATTR(priority, 0644, wq_priority_show, wq_priority_store);
> +
> +static ssize_t wq_type_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	switch (wq->type) {
> +	case IDXD_WQT_KERNEL:
> +		return sprintf(buf, "%s\n",
> +			       idxd_wq_type_names[IDXD_WQT_KERNEL]);
> +	case IDXD_WQT_NONE:
> +	default:
> +		return sprintf(buf, "%s\n",
> +			       idxd_wq_type_names[IDXD_WQT_NONE]);
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static ssize_t wq_type_store(struct device *dev,
> +			     struct device_attribute *attr, const char *buf,
> +			     size_t count)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +	enum idxd_wq_type old_type;
> +
> +	if (wq->state != IDXD_WQ_DISABLED)
> +		return -EPERM;
> +
> +	old_type = wq->type;
> +	if (sysfs_streq(buf, idxd_wq_type_names[IDXD_WQT_KERNEL]))
> +		wq->type = IDXD_WQT_KERNEL;
> +	else
> +		wq->type = IDXD_WQT_NONE;
> +
> +	/* If we are changing queue type, clear the name */
> +	if (wq->type != old_type)
> +		memset(wq->name, 0, WQ_NAME_SIZE + 1);
> +
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_wq_type =
> +		__ATTR(type, 0644, wq_type_show, wq_type_store);
> +
> +static ssize_t wq_name_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	return sprintf(buf, "%s\n", wq->name);
> +}
> +
> +static ssize_t wq_name_store(struct device *dev,
> +			     struct device_attribute *attr, const char *buf,
> +			     size_t count)
> +{
> +	struct idxd_wq *wq = container_of(dev, struct idxd_wq, conf_dev);
> +
> +	if (wq->state != IDXD_WQ_DISABLED)
> +		return -EPERM;
> +
> +	if (strlen(buf) > WQ_NAME_SIZE || strlen(buf) == 0)
> +		return -EINVAL;
> +
> +	memset(wq->name, 0, WQ_NAME_SIZE + 1);
> +	strncpy(wq->name, buf, WQ_NAME_SIZE);
> +	strreplace(wq->name, '\n', '\0');
> +	return count;
> +}
> +
> +static struct device_attribute dev_attr_wq_name =
> +		__ATTR(name, 0644, wq_name_show, wq_name_store);
> +
> +static struct attribute *idxd_wq_attributes[] = {
> +	&dev_attr_wq_clients.attr,
> +	&dev_attr_wq_state.attr,
> +	&dev_attr_wq_group_id.attr,
> +	&dev_attr_wq_mode.attr,
> +	&dev_attr_wq_size.attr,
> +	&dev_attr_wq_priority.attr,
> +	&dev_attr_wq_type.attr,
> +	&dev_attr_wq_name.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group idxd_wq_attribute_group = {
> +	.attrs = idxd_wq_attributes,
> +};
> +
> +static const struct attribute_group *idxd_wq_attribute_groups[] = {
> +	&idxd_wq_attribute_group,
> +	NULL,
> +};
> +
> +/* IDXD device attribs */
> +static ssize_t max_work_queues_size_show(struct device *dev,
> +					 struct device_attribute *attr,
> +					 char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->max_wq_size);
> +}
> +static DEVICE_ATTR_RO(max_work_queues_size);
> +
> +static ssize_t max_groups_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->max_groups);
> +}
> +static DEVICE_ATTR_RO(max_groups);
> +
> +static ssize_t max_work_queues_show(struct device *dev,
> +				    struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->max_wqs);
> +}
> +static DEVICE_ATTR_RO(max_work_queues);
> +
> +static ssize_t max_engines_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->max_engines);
> +}
> +static DEVICE_ATTR_RO(max_engines);
> +
> +static ssize_t numa_node_show(struct device *dev,
> +			      struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%d\n", dev_to_node(&idxd->pdev->dev));
> +}
> +static DEVICE_ATTR_RO(numa_node);
> +
> +static ssize_t max_batch_size_show(struct device *dev,
> +				   struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->max_batch_size);
> +}
> +static DEVICE_ATTR_RO(max_batch_size);
> +
> +static ssize_t max_transfer_size_show(struct device *dev,
> +				      struct device_attribute *attr,
> +				      char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%llu\n", idxd->max_xfer_bytes);
> +}
> +static DEVICE_ATTR_RO(max_transfer_size);
> +
> +static ssize_t op_cap_show(struct device *dev,
> +			   struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%#llx\n", idxd->hw.opcap.bits[0]);
> +}
> +static DEVICE_ATTR_RO(op_cap);
> +
> +static ssize_t configurable_show(struct device *dev,
> +				 struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n",
> +			test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags));
> +}
> +static DEVICE_ATTR_RO(configurable);
> +
> +static ssize_t clients_show(struct device *dev,
> +			    struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +	unsigned long flags;
> +	int count = 0, i;
> +
> +	spin_lock_irqsave(&idxd->dev_lock, flags);
> +	for (i = 0; i < idxd->max_wqs; i++) {
> +		struct idxd_wq *wq = &idxd->wqs[i];
> +
> +		count += wq->client_count;
> +	}
> +	spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +
> +	return sprintf(buf, "%d\n", count);
> +}
> +static DEVICE_ATTR_RO(clients);
> +
> +static ssize_t state_show(struct device *dev,
> +			  struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	switch (idxd->state) {
> +	case IDXD_DEV_DISABLED:
> +	case IDXD_DEV_CONF_READY:
> +		return sprintf(buf, "disabled\n");
> +	case IDXD_DEV_ENABLED:
> +		return sprintf(buf, "enabled\n");
> +	case IDXD_DEV_HALTED:
> +		return sprintf(buf, "halted\n");
> +	}
> +
> +	return sprintf(buf, "unknown\n");
> +}
> +static DEVICE_ATTR_RO(state);
> +
> +static ssize_t errors_show(struct device *dev,
> +			   struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +	int i, out = 0;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&idxd->dev_lock, flags);
> +	for (i = 0; i < 4; i++)
> +		out += sprintf(buf + out, "%#018llx ", idxd->sw_err.bits[i]);
> +	spin_unlock_irqrestore(&idxd->dev_lock, flags);
> +	out--;
> +	out += sprintf(buf + out, "\n");
> +	return out;
> +}
> +static DEVICE_ATTR_RO(errors);
> +
> +static ssize_t max_tokens_show(struct device *dev,
> +			       struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->max_tokens);
> +}
> +static DEVICE_ATTR_RO(max_tokens);
> +
> +static ssize_t token_limit_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +
> +	return sprintf(buf, "%u\n", idxd->token_limit);
> +}
> +
> +static ssize_t token_limit_store(struct device *dev,
> +				 struct device_attribute *attr,
> +				 const char *buf, size_t count)
> +{
> +	struct idxd_device *idxd =
> +		container_of(dev, struct idxd_device, conf_dev);
> +	unsigned long val;
> +	int rc;
> +
> +	rc = kstrtoul(buf, 10, &val);
> +	if (rc < 0)
> +		return -EINVAL;
> +
> +	if (idxd->state == IDXD_DEV_ENABLED)
> +		return -EPERM;
> +
> +	if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
> +		return -EPERM;
> +
> +	if (!idxd->hw.group_cap.token_limit)
> +		return -EPERM;
> +
> +	if (val > idxd->hw.group_cap.total_tokens)
> +		return -EINVAL;
> +
> +	idxd->token_limit = val;
> +	return count;
> +}
> +static DEVICE_ATTR_RW(token_limit);
> +
> +static struct attribute *idxd_device_attributes[] = {
> +	&dev_attr_max_groups.attr,
> +	&dev_attr_max_work_queues.attr,
> +	&dev_attr_max_work_queues_size.attr,
> +	&dev_attr_max_engines.attr,
> +	&dev_attr_numa_node.attr,
> +	&dev_attr_max_batch_size.attr,
> +	&dev_attr_max_transfer_size.attr,
> +	&dev_attr_op_cap.attr,
> +	&dev_attr_configurable.attr,
> +	&dev_attr_clients.attr,
> +	&dev_attr_state.attr,
> +	&dev_attr_errors.attr,
> +	&dev_attr_max_tokens.attr,
> +	&dev_attr_token_limit.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group idxd_device_attribute_group = {
> +	.attrs = idxd_device_attributes,
> +};
> +
> +static const struct attribute_group *idxd_attribute_groups[] = {
> +	&idxd_device_attribute_group,
> +	NULL,
> +};
> +
> +static int idxd_setup_engine_sysfs(struct idxd_device *idxd)
> +{
> +	struct device *dev = &idxd->pdev->dev;
> +	int i, rc;
> +
> +	for (i = 0; i < idxd->max_engines; i++) {
> +		struct idxd_engine *engine = &idxd->engines[i];
> +
> +		engine->conf_dev.parent = &idxd->conf_dev;
> +		dev_set_name(&engine->conf_dev, "engine%d.%d",
> +			     idxd->id, engine->id);
> +		engine->conf_dev.bus = idxd_get_bus_type(idxd);
> +		engine->conf_dev.groups = idxd_engine_attribute_groups;
> +		engine->conf_dev.type = &idxd_engine_device_type;
> +		dev_dbg(dev, "Engine device register: %s\n",
> +			dev_name(&engine->conf_dev));
> +		rc = device_register(&engine->conf_dev);
> +		if (rc < 0) {
> +			put_device(&engine->conf_dev);
> +			goto cleanup;
> +		}
> +	}
> +
> +	return 0;
> +
> +cleanup:
> +	while (i--) {
> +		struct idxd_engine *engine = &idxd->engines[i];
> +
> +		device_unregister(&engine->conf_dev);
> +	}
> +	return rc;
> +}
> +
> +static int idxd_setup_group_sysfs(struct idxd_device *idxd)
> +{
> +	struct device *dev = &idxd->pdev->dev;
> +	int i, rc;
> +
> +	for (i = 0; i < idxd->max_groups; i++) {
> +		struct idxd_group *group = &idxd->groups[i];
> +
> +		group->conf_dev.parent = &idxd->conf_dev;
> +		dev_set_name(&group->conf_dev, "group%d.%d",
> +			     idxd->id, group->id);
> +		group->conf_dev.bus = idxd_get_bus_type(idxd);
> +		group->conf_dev.groups = idxd_group_attribute_groups;
> +		group->conf_dev.type = &idxd_group_device_type;
> +		dev_dbg(dev, "Group device register: %s\n",
> +			dev_name(&group->conf_dev));
> +		rc = device_register(&group->conf_dev);
> +		if (rc < 0) {
> +			put_device(&group->conf_dev);
> +			goto cleanup;
> +		}
> +	}
> +
> +	return 0;
> +
> +cleanup:
> +	while (i--) {
> +		struct idxd_group *group = &idxd->groups[i];
> +
> +		device_unregister(&group->conf_dev);
> +	}
> +	return rc;
> +}
> +
> +static int idxd_setup_wq_sysfs(struct idxd_device *idxd)
> +{
> +	struct device *dev = &idxd->pdev->dev;
> +	int i, rc;
> +
> +	for (i = 0; i < idxd->max_wqs; i++) {
> +		struct idxd_wq *wq = &idxd->wqs[i];
> +
> +		wq->conf_dev.parent = &idxd->conf_dev;
> +		dev_set_name(&wq->conf_dev, "wq%d.%d", idxd->id, wq->id);
> +		wq->conf_dev.bus = idxd_get_bus_type(idxd);
> +		wq->conf_dev.groups = idxd_wq_attribute_groups;
> +		wq->conf_dev.type = &idxd_wq_device_type;
> +		dev_dbg(dev, "WQ device register: %s\n",
> +			dev_name(&wq->conf_dev));
> +		rc = device_register(&wq->conf_dev);
> +		if (rc < 0) {
> +			put_device(&wq->conf_dev);
> +			goto cleanup;
> +		}
> +	}
> +
> +	return 0;
> +
> +cleanup:
> +	while (i--) {
> +		struct idxd_wq *wq = &idxd->wqs[i];
> +
> +		device_unregister(&wq->conf_dev);
> +	}
> +	return rc;
> +}
> +
> +static int idxd_setup_device_sysfs(struct idxd_device *idxd)
> +{
> +	struct device *dev = &idxd->pdev->dev;
> +	int rc;
> +	char devname[IDXD_NAME_SIZE];
> +
> +	sprintf(devname, "%s%d", idxd_get_dev_name(idxd), idxd->id);
> +	idxd->conf_dev.parent = dev;
> +	dev_set_name(&idxd->conf_dev, "%s", devname);
> +	idxd->conf_dev.bus = idxd_get_bus_type(idxd);
> +	idxd->conf_dev.groups = idxd_attribute_groups;
> +	idxd->conf_dev.type = idxd_get_device_type(idxd);
> +
> +	dev_dbg(dev, "IDXD device register: %s\n", dev_name(&idxd->conf_dev));
> +	rc = device_register(&idxd->conf_dev);
> +	if (rc < 0) {
> +		put_device(&idxd->conf_dev);
> +		return rc;
> +	}
> +
> +	return 0;
> +}
> +
> +int idxd_setup_sysfs(struct idxd_device *idxd)
> +{
> +	struct device *dev = &idxd->pdev->dev;
> +	int rc;
> +
> +	rc = idxd_setup_device_sysfs(idxd);
> +	if (rc < 0) {
> +		dev_dbg(dev, "Device sysfs registering failed: %d\n", rc);
> +		return rc;
> +	}
> +
> +	rc = idxd_setup_wq_sysfs(idxd);
> +	if (rc < 0) {
> +		/* unregister conf dev */
> +		dev_dbg(dev, "Work Queue sysfs registering failed: %d\n", rc);
> +		return rc;
> +	}
> +
> +	rc = idxd_setup_group_sysfs(idxd);
> +	if (rc < 0) {
> +		/* unregister conf dev */
> +		dev_dbg(dev, "Group sysfs registering failed: %d\n", rc);
> +		return rc;
> +	}
> +
> +	rc = idxd_setup_engine_sysfs(idxd);
> +	if (rc < 0) {
> +		/* unregister conf dev */
> +		dev_dbg(dev, "Engine sysfs registering failed: %d\n", rc);
> +		return rc;
> +	}
> +
> +	return 0;
> +}
> +
> +void idxd_cleanup_sysfs(struct idxd_device *idxd)
> +{
> +	int i;
> +
> +	for (i = 0; i < idxd->max_wqs; i++) {
> +		struct idxd_wq *wq = &idxd->wqs[i];
> +
> +		device_unregister(&wq->conf_dev);
> +	}
> +
> +	for (i = 0; i < idxd->max_engines; i++) {
> +		struct idxd_engine *engine = &idxd->engines[i];
> +
> +		device_unregister(&engine->conf_dev);
> +	}
> +
> +	for (i = 0; i < idxd->max_groups; i++) {
> +		struct idxd_group *group = &idxd->groups[i];
> +
> +		device_unregister(&group->conf_dev);
> +	}
> +
> +	device_unregister(&idxd->conf_dev);
> +}
> +
> +int idxd_register_bus_type(void)
> +{
> +	int i, rc;
> +
> +	for (i = 0; i < IDXD_TYPE_MAX; i++) {
> +		rc = bus_register(idxd_bus_types[i]);
> +		if (rc < 0)
> +			goto bus_err;
> +	}
> +
> +	return 0;
> +
> +bus_err:
> +	for (; i > 0; i--)
> +		bus_unregister(idxd_bus_types[i]);
> +	return rc;
> +}
> +
> +void idxd_unregister_bus_type(void)
> +{
> +	int i;
> +
> +	for (i = 0; i < IDXD_TYPE_MAX; i++)
> +		bus_unregister(idxd_bus_types[i]);
> +}

-- 
~Vinod