diff mbox series

[v4,04/18] nitro_enclaves: Init PCI device driver

Message ID 20200622200329.52996-5-andraprs@amazon.com (mailing list archive)
State New, archived
Headers show
Series Add support for Nitro Enclaves | expand

Commit Message

Paraschiv, Andra-Irina June 22, 2020, 8:03 p.m. UTC
The Nitro Enclaves PCI device is used by the kernel driver as a means of
communication with the hypervisor on the host where the primary VM and
the enclaves run. It handles requests with regard to enclave lifetime.

Setup the PCI device driver and add support for MSI-X interrupts.

Signed-off-by: Alexandru-Catalin Vasile <lexnv@amazon.com>
Signed-off-by: Alexandru Ciobotaru <alcioa@amazon.com>
Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
---
Changelog

v3 -> v4

* Use dev_err instead of custom NE log pattern.
* Update NE PCI driver name to "nitro_enclaves".

v2 -> v3

* Remove the GPL additional wording as SPDX-License-Identifier is
  already in place.
* Remove the WARN_ON calls.
* Remove linux/bug include that is not needed.
* Update static calls sanity checks.
* Remove "ratelimited" from the logs that are not in the ioctl call
  paths.
* Update kzfree() calls to kfree().

v1 -> v2

* Add log pattern for NE.
* Update PCI device setup functions to receive PCI device data structure and
  then get private data from it inside the functions logic.
* Remove the BUG_ON calls.
* Add teardown function for MSI-X setup.
* Update goto labels to match their purpose.
* Implement TODO for NE PCI device disable state check.
* Update function name for NE PCI device probe / remove.
---
 drivers/virt/nitro_enclaves/ne_pci_dev.c | 261 +++++++++++++++++++++++
 1 file changed, 261 insertions(+)
 create mode 100644 drivers/virt/nitro_enclaves/ne_pci_dev.c

Comments

Alexander Graf July 2, 2020, 3:09 p.m. UTC | #1
On 22.06.20 22:03, Andra Paraschiv wrote:
> The Nitro Enclaves PCI device is used by the kernel driver as a means of
> communication with the hypervisor on the host where the primary VM and
> the enclaves run. It handles requests with regard to enclave lifetime.
> 
> Setup the PCI device driver and add support for MSI-X interrupts.
> 
> Signed-off-by: Alexandru-Catalin Vasile <lexnv@amazon.com>
> Signed-off-by: Alexandru Ciobotaru <alcioa@amazon.com>
> Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
> ---
> Changelog
> 
> v3 -> v4
> 
> * Use dev_err instead of custom NE log pattern.
> * Update NE PCI driver name to "nitro_enclaves".
> 
> v2 -> v3
> 
> * Remove the GPL additional wording as SPDX-License-Identifier is
>    already in place.
> * Remove the WARN_ON calls.
> * Remove linux/bug include that is not needed.
> * Update static calls sanity checks.
> * Remove "ratelimited" from the logs that are not in the ioctl call
>    paths.
> * Update kzfree() calls to kfree().
> 
> v1 -> v2
> 
> * Add log pattern for NE.
> * Update PCI device setup functions to receive PCI device data structure and
>    then get private data from it inside the functions logic.
> * Remove the BUG_ON calls.
> * Add teardown function for MSI-X setup.
> * Update goto labels to match their purpose.
> * Implement TODO for NE PCI device disable state check.
> * Update function name for NE PCI device probe / remove.
> ---
>   drivers/virt/nitro_enclaves/ne_pci_dev.c | 261 +++++++++++++++++++++++
>   1 file changed, 261 insertions(+)
>   create mode 100644 drivers/virt/nitro_enclaves/ne_pci_dev.c
> 
> diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.c b/drivers/virt/nitro_enclaves/ne_pci_dev.c
> new file mode 100644
> index 000000000000..235fa3ecbee2
> --- /dev/null
> +++ b/drivers/virt/nitro_enclaves/ne_pci_dev.c
> @@ -0,0 +1,261 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
> + */
> +
> +/* Nitro Enclaves (NE) PCI device driver. */
> +
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/list.h>
> +#include <linux/mutex.h>
> +#include <linux/module.h>
> +#include <linux/nitro_enclaves.h>
> +#include <linux/pci.h>
> +#include <linux/types.h>
> +#include <linux/wait.h>
> +
> +#include "ne_misc_dev.h"
> +#include "ne_pci_dev.h"
> +
> +#define NE_DEFAULT_TIMEOUT_MSECS (120000) /* 120 sec */
> +
> +static const struct pci_device_id ne_pci_ids[] = {
> +	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, PCI_DEVICE_ID_NE) },
> +	{ 0, }
> +};
> +
> +MODULE_DEVICE_TABLE(pci, ne_pci_ids);
> +
> +/**
> + * ne_setup_msix - Setup MSI-X vectors for the PCI device.
> + *
> + * @pdev: PCI device to setup the MSI-X for.
> + *
> + * @returns: 0 on success, negative return value on failure.
> + */
> +static int ne_setup_msix(struct pci_dev *pdev)
> +{
> +	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
> +	int nr_vecs = 0;
> +	int rc = -EINVAL;
> +
> +	if (!ne_pci_dev)
> +		return -EINVAL;
> +
> +	nr_vecs = pci_msix_vec_count(pdev);
> +	if (nr_vecs < 0) {
> +		rc = nr_vecs;
> +
> +		dev_err(&pdev->dev, "Error in getting vec count [rc=%d]\n", rc);
> +
> +		return rc;
> +	}
> +
> +	rc = pci_alloc_irq_vectors(pdev, nr_vecs, nr_vecs, PCI_IRQ_MSIX);
> +	if (rc < 0) {
> +		dev_err(&pdev->dev, "Error in alloc MSI-X vecs [rc=%d]\n", rc);
> +
> +		return rc;
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * ne_teardown_msix - Teardown MSI-X vectors for the PCI device.
> + *
> + * @pdev: PCI device to teardown the MSI-X for.
> + */
> +static void ne_teardown_msix(struct pci_dev *pdev)
> +{
> +	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
> +
> +	if (!ne_pci_dev)
> +		return;
> +
> +	pci_free_irq_vectors(pdev);
> +}
> +
> +/**
> + * ne_pci_dev_enable - Select PCI device version and enable it.
> + *
> + * @pdev: PCI device to select version for and then enable.
> + *
> + * @returns: 0 on success, negative return value on failure.
> + */
> +static int ne_pci_dev_enable(struct pci_dev *pdev)
> +{
> +	u8 dev_enable_reply = 0;
> +	u16 dev_version_reply = 0;
> +	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
> +
> +	if (!ne_pci_dev || !ne_pci_dev->iomem_base)
> +		return -EINVAL;

How can this ever happen?

> +
> +	iowrite16(NE_VERSION_MAX, ne_pci_dev->iomem_base + NE_VERSION);
> +
> +	dev_version_reply = ioread16(ne_pci_dev->iomem_base + NE_VERSION);
> +	if (dev_version_reply != NE_VERSION_MAX) {
> +		dev_err(&pdev->dev, "Error in pci dev version cmd\n");
> +
> +		return -EIO;
> +	}
> +
> +	iowrite8(NE_ENABLE_ON, ne_pci_dev->iomem_base + NE_ENABLE);
> +
> +	dev_enable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
> +	if (dev_enable_reply != NE_ENABLE_ON) {
> +		dev_err(&pdev->dev, "Error in pci dev enable cmd\n");
> +
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +/**
> + * ne_pci_dev_disable - Disable PCI device.
> + *
> + * @pdev: PCI device to disable.
> + */
> +static void ne_pci_dev_disable(struct pci_dev *pdev)
> +{
> +	u8 dev_disable_reply = 0;
> +	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
> +	const unsigned int sleep_time = 10; /* 10 ms */
> +	unsigned int sleep_time_count = 0;
> +
> +	if (!ne_pci_dev || !ne_pci_dev->iomem_base)
> +		return;

How can this ever happen?


Alex



Amazon Development Center Germany GmbH
Krausenstr. 38
10117 Berlin
Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Sitz: Berlin
Ust-ID: DE 289 237 879
Paraschiv, Andra-Irina July 4, 2020, 10 a.m. UTC | #2
On 02/07/2020 18:09, Alexander Graf wrote:
>
>
> On 22.06.20 22:03, Andra Paraschiv wrote:
>> The Nitro Enclaves PCI device is used by the kernel driver as a means of
>> communication with the hypervisor on the host where the primary VM and
>> the enclaves run. It handles requests with regard to enclave lifetime.
>>
>> Setup the PCI device driver and add support for MSI-X interrupts.
>>
>> Signed-off-by: Alexandru-Catalin Vasile <lexnv@amazon.com>
>> Signed-off-by: Alexandru Ciobotaru <alcioa@amazon.com>
>> Signed-off-by: Andra Paraschiv <andraprs@amazon.com>
>> ---
>> Changelog
>>
>> v3 -> v4
>>
>> * Use dev_err instead of custom NE log pattern.
>> * Update NE PCI driver name to "nitro_enclaves".
>>
>> v2 -> v3
>>
>> * Remove the GPL additional wording as SPDX-License-Identifier is
>>    already in place.
>> * Remove the WARN_ON calls.
>> * Remove linux/bug include that is not needed.
>> * Update static calls sanity checks.
>> * Remove "ratelimited" from the logs that are not in the ioctl call
>>    paths.
>> * Update kzfree() calls to kfree().
>>
>> v1 -> v2
>>
>> * Add log pattern for NE.
>> * Update PCI device setup functions to receive PCI device data 
>> structure and
>>    then get private data from it inside the functions logic.
>> * Remove the BUG_ON calls.
>> * Add teardown function for MSI-X setup.
>> * Update goto labels to match their purpose.
>> * Implement TODO for NE PCI device disable state check.
>> * Update function name for NE PCI device probe / remove.
>> ---
>>   drivers/virt/nitro_enclaves/ne_pci_dev.c | 261 +++++++++++++++++++++++
>>   1 file changed, 261 insertions(+)
>>   create mode 100644 drivers/virt/nitro_enclaves/ne_pci_dev.c
>>
>> diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.c 
>> b/drivers/virt/nitro_enclaves/ne_pci_dev.c
>> new file mode 100644
>> index 000000000000..235fa3ecbee2
>> --- /dev/null
>> +++ b/drivers/virt/nitro_enclaves/ne_pci_dev.c
>> @@ -0,0 +1,261 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights 
>> Reserved.
>> + */
>> +
>> +/* Nitro Enclaves (NE) PCI device driver. */
>> +
>> +#include <linux/delay.h>
>> +#include <linux/device.h>
>> +#include <linux/list.h>
>> +#include <linux/mutex.h>
>> +#include <linux/module.h>
>> +#include <linux/nitro_enclaves.h>
>> +#include <linux/pci.h>
>> +#include <linux/types.h>
>> +#include <linux/wait.h>
>> +
>> +#include "ne_misc_dev.h"
>> +#include "ne_pci_dev.h"
>> +
>> +#define NE_DEFAULT_TIMEOUT_MSECS (120000) /* 120 sec */
>> +
>> +static const struct pci_device_id ne_pci_ids[] = {
>> +    { PCI_DEVICE(PCI_VENDOR_ID_AMAZON, PCI_DEVICE_ID_NE) },
>> +    { 0, }
>> +};
>> +
>> +MODULE_DEVICE_TABLE(pci, ne_pci_ids);
>> +
>> +/**
>> + * ne_setup_msix - Setup MSI-X vectors for the PCI device.
>> + *
>> + * @pdev: PCI device to setup the MSI-X for.
>> + *
>> + * @returns: 0 on success, negative return value on failure.
>> + */
>> +static int ne_setup_msix(struct pci_dev *pdev)
>> +{
>> +    struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
>> +    int nr_vecs = 0;
>> +    int rc = -EINVAL;
>> +
>> +    if (!ne_pci_dev)
>> +        return -EINVAL;
>> +
>> +    nr_vecs = pci_msix_vec_count(pdev);
>> +    if (nr_vecs < 0) {
>> +        rc = nr_vecs;
>> +
>> +        dev_err(&pdev->dev, "Error in getting vec count [rc=%d]\n", 
>> rc);
>> +
>> +        return rc;
>> +    }
>> +
>> +    rc = pci_alloc_irq_vectors(pdev, nr_vecs, nr_vecs, PCI_IRQ_MSIX);
>> +    if (rc < 0) {
>> +        dev_err(&pdev->dev, "Error in alloc MSI-X vecs [rc=%d]\n", rc);
>> +
>> +        return rc;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +/**
>> + * ne_teardown_msix - Teardown MSI-X vectors for the PCI device.
>> + *
>> + * @pdev: PCI device to teardown the MSI-X for.
>> + */
>> +static void ne_teardown_msix(struct pci_dev *pdev)
>> +{
>> +    struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
>> +
>> +    if (!ne_pci_dev)
>> +        return;
>> +
>> +    pci_free_irq_vectors(pdev);
>> +}
>> +
>> +/**
>> + * ne_pci_dev_enable - Select PCI device version and enable it.
>> + *
>> + * @pdev: PCI device to select version for and then enable.
>> + *
>> + * @returns: 0 on success, negative return value on failure.
>> + */
>> +static int ne_pci_dev_enable(struct pci_dev *pdev)
>> +{
>> +    u8 dev_enable_reply = 0;
>> +    u16 dev_version_reply = 0;
>> +    struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
>> +
>> +    if (!ne_pci_dev || !ne_pci_dev->iomem_base)
>> +        return -EINVAL;
>
> How can this ever happen?

This check and the following one are part of that checks added before 
for the situations that shouldn't happen, only if buggy system or broken 
logic at all. Removed the checks.

Thanks,
Andra

>
>> +
>> +    iowrite16(NE_VERSION_MAX, ne_pci_dev->iomem_base + NE_VERSION);
>> +
>> +    dev_version_reply = ioread16(ne_pci_dev->iomem_base + NE_VERSION);
>> +    if (dev_version_reply != NE_VERSION_MAX) {
>> +        dev_err(&pdev->dev, "Error in pci dev version cmd\n");
>> +
>> +        return -EIO;
>> +    }
>> +
>> +    iowrite8(NE_ENABLE_ON, ne_pci_dev->iomem_base + NE_ENABLE);
>> +
>> +    dev_enable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
>> +    if (dev_enable_reply != NE_ENABLE_ON) {
>> +        dev_err(&pdev->dev, "Error in pci dev enable cmd\n");
>> +
>> +        return -EIO;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +/**
>> + * ne_pci_dev_disable - Disable PCI device.
>> + *
>> + * @pdev: PCI device to disable.
>> + */
>> +static void ne_pci_dev_disable(struct pci_dev *pdev)
>> +{
>> +    u8 dev_disable_reply = 0;
>> +    struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
>> +    const unsigned int sleep_time = 10; /* 10 ms */
>> +    unsigned int sleep_time_count = 0;
>> +
>> +    if (!ne_pci_dev || !ne_pci_dev->iomem_base)
>> +        return;
>
> How can this ever happen?
>
>
> Alex




Amazon Development Center (Romania) S.R.L. registered office: 27A Sf. Lazar Street, UBC5, floor 2, Iasi, Iasi County, 700045, Romania. Registered in Romania. Registration number J22/2621/2005.
diff mbox series

Patch

diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.c b/drivers/virt/nitro_enclaves/ne_pci_dev.c
new file mode 100644
index 000000000000..235fa3ecbee2
--- /dev/null
+++ b/drivers/virt/nitro_enclaves/ne_pci_dev.c
@@ -0,0 +1,261 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ */
+
+/* Nitro Enclaves (NE) PCI device driver. */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/module.h>
+#include <linux/nitro_enclaves.h>
+#include <linux/pci.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+
+#include "ne_misc_dev.h"
+#include "ne_pci_dev.h"
+
+#define NE_DEFAULT_TIMEOUT_MSECS (120000) /* 120 sec */
+
+static const struct pci_device_id ne_pci_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_AMAZON, PCI_DEVICE_ID_NE) },
+	{ 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, ne_pci_ids);
+
+/**
+ * ne_setup_msix - Setup MSI-X vectors for the PCI device.
+ *
+ * @pdev: PCI device to setup the MSI-X for.
+ *
+ * @returns: 0 on success, negative return value on failure.
+ */
+static int ne_setup_msix(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+	int nr_vecs = 0;
+	int rc = -EINVAL;
+
+	if (!ne_pci_dev)
+		return -EINVAL;
+
+	nr_vecs = pci_msix_vec_count(pdev);
+	if (nr_vecs < 0) {
+		rc = nr_vecs;
+
+		dev_err(&pdev->dev, "Error in getting vec count [rc=%d]\n", rc);
+
+		return rc;
+	}
+
+	rc = pci_alloc_irq_vectors(pdev, nr_vecs, nr_vecs, PCI_IRQ_MSIX);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in alloc MSI-X vecs [rc=%d]\n", rc);
+
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * ne_teardown_msix - Teardown MSI-X vectors for the PCI device.
+ *
+ * @pdev: PCI device to teardown the MSI-X for.
+ */
+static void ne_teardown_msix(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	if (!ne_pci_dev)
+		return;
+
+	pci_free_irq_vectors(pdev);
+}
+
+/**
+ * ne_pci_dev_enable - Select PCI device version and enable it.
+ *
+ * @pdev: PCI device to select version for and then enable.
+ *
+ * @returns: 0 on success, negative return value on failure.
+ */
+static int ne_pci_dev_enable(struct pci_dev *pdev)
+{
+	u8 dev_enable_reply = 0;
+	u16 dev_version_reply = 0;
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	if (!ne_pci_dev || !ne_pci_dev->iomem_base)
+		return -EINVAL;
+
+	iowrite16(NE_VERSION_MAX, ne_pci_dev->iomem_base + NE_VERSION);
+
+	dev_version_reply = ioread16(ne_pci_dev->iomem_base + NE_VERSION);
+	if (dev_version_reply != NE_VERSION_MAX) {
+		dev_err(&pdev->dev, "Error in pci dev version cmd\n");
+
+		return -EIO;
+	}
+
+	iowrite8(NE_ENABLE_ON, ne_pci_dev->iomem_base + NE_ENABLE);
+
+	dev_enable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
+	if (dev_enable_reply != NE_ENABLE_ON) {
+		dev_err(&pdev->dev, "Error in pci dev enable cmd\n");
+
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/**
+ * ne_pci_dev_disable - Disable PCI device.
+ *
+ * @pdev: PCI device to disable.
+ */
+static void ne_pci_dev_disable(struct pci_dev *pdev)
+{
+	u8 dev_disable_reply = 0;
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+	const unsigned int sleep_time = 10; /* 10 ms */
+	unsigned int sleep_time_count = 0;
+
+	if (!ne_pci_dev || !ne_pci_dev->iomem_base)
+		return;
+
+	iowrite8(NE_ENABLE_OFF, ne_pci_dev->iomem_base + NE_ENABLE);
+
+	/*
+	 * Check for NE_ENABLE_OFF in a loop, to handle cases when the device
+	 * state is not immediately set to disabled and going through a
+	 * transitory state of disabling.
+	 */
+	while (sleep_time_count < NE_DEFAULT_TIMEOUT_MSECS) {
+		dev_disable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
+		if (dev_disable_reply == NE_ENABLE_OFF)
+			return;
+
+		msleep_interruptible(sleep_time);
+		sleep_time_count += sleep_time;
+	}
+
+	dev_disable_reply = ioread8(ne_pci_dev->iomem_base + NE_ENABLE);
+	if (dev_disable_reply != NE_ENABLE_OFF)
+		dev_err(&pdev->dev, "Error in pci dev disable cmd\n");
+}
+
+static int ne_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct ne_pci_dev *ne_pci_dev = NULL;
+	int rc = -EINVAL;
+
+	ne_pci_dev = kzalloc(sizeof(*ne_pci_dev), GFP_KERNEL);
+	if (!ne_pci_dev)
+		return -ENOMEM;
+
+	rc = pci_enable_device(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in pci dev enable [rc=%d]\n", rc);
+
+		goto free_ne_pci_dev;
+	}
+
+	rc = pci_request_regions_exclusive(pdev, "ne_pci_dev");
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in pci request regions [rc=%d]\n",
+			rc);
+
+		goto disable_pci_dev;
+	}
+
+	ne_pci_dev->iomem_base = pci_iomap(pdev, PCI_BAR_NE, 0);
+	if (!ne_pci_dev->iomem_base) {
+		rc = -ENOMEM;
+
+		dev_err(&pdev->dev, "Error in pci iomap [rc=%d]\n", rc);
+
+		goto release_pci_regions;
+	}
+
+	pci_set_drvdata(pdev, ne_pci_dev);
+
+	rc = ne_setup_msix(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in pci dev msix setup [rc=%d]\n",
+			rc);
+
+		goto iounmap_pci_bar;
+	}
+
+	ne_pci_dev_disable(pdev);
+
+	rc = ne_pci_dev_enable(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "Error in ne_pci_dev enable [rc=%d]\n",
+			rc);
+
+		goto teardown_msix;
+	}
+
+	atomic_set(&ne_pci_dev->cmd_reply_avail, 0);
+	init_waitqueue_head(&ne_pci_dev->cmd_reply_wait_q);
+	INIT_LIST_HEAD(&ne_pci_dev->enclaves_list);
+	mutex_init(&ne_pci_dev->enclaves_list_mutex);
+	mutex_init(&ne_pci_dev->pci_dev_mutex);
+	ne_pci_dev->pdev = pdev;
+
+	return 0;
+
+teardown_msix:
+	ne_teardown_msix(pdev);
+iounmap_pci_bar:
+	pci_set_drvdata(pdev, NULL);
+	pci_iounmap(pdev, ne_pci_dev->iomem_base);
+release_pci_regions:
+	pci_release_regions(pdev);
+disable_pci_dev:
+	pci_disable_device(pdev);
+free_ne_pci_dev:
+	kfree(ne_pci_dev);
+
+	return rc;
+}
+
+static void ne_pci_remove(struct pci_dev *pdev)
+{
+	struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev);
+
+	if (!ne_pci_dev || !ne_pci_dev->iomem_base)
+		return;
+
+	ne_pci_dev_disable(pdev);
+
+	ne_teardown_msix(pdev);
+
+	pci_set_drvdata(pdev, NULL);
+
+	pci_iounmap(pdev, ne_pci_dev->iomem_base);
+
+	pci_release_regions(pdev);
+
+	pci_disable_device(pdev);
+
+	kfree(ne_pci_dev);
+}
+
+/*
+ * TODO: Add suspend / resume functions for power management w/ CONFIG_PM, if
+ * needed.
+ */
+struct pci_driver ne_pci_driver = {
+	.name		= "nitro_enclaves",
+	.id_table	= ne_pci_ids,
+	.probe		= ne_pci_probe,
+	.remove		= ne_pci_remove,
+};