diff mbox

[v13,02/22] vfio: VFIO based driver for Mediated devices

Message ID 1479223805-22895-3-git-send-email-kwankhede@nvidia.com (mailing list archive)
State New, archived
Headers show

Commit Message

Kirti Wankhede Nov. 15, 2016, 3:29 p.m. UTC
vfio_mdev driver registers with mdev core driver.
mdev core driver creates mediated device and calls probe routine of
vfio_mdev driver for each device.
Probe routine of vfio_mdev driver adds mediated device to VFIO core module

This driver forms a shim layer that pass through VFIO devices operations
to vendor driver for mediated devices.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Jike Song <jike.song@intel.com>

Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
---
 drivers/vfio/mdev/Kconfig     |   7 ++
 drivers/vfio/mdev/Makefile    |   1 +
 drivers/vfio/mdev/mdev_core.c |  16 ++++-
 drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 171 insertions(+), 1 deletion(-)
 create mode 100644 drivers/vfio/mdev/vfio_mdev.c

Comments

Kirti Wankhede Nov. 16, 2016, 3:05 p.m. UTC | #1
On 11/16/2016 7:59 AM, Dong Jia Shi wrote:
> * Kirti Wankhede <kwankhede@nvidia.com> [2016-11-15 20:59:45 +0530]:
> 
> Hi Kirti,
> 
>> vfio_mdev driver registers with mdev core driver.
>> mdev core driver creates mediated device and calls probe routine of
>> vfio_mdev driver for each device.
>> Probe routine of vfio_mdev driver adds mediated device to VFIO core module
>>
>> This driver forms a shim layer that pass through VFIO devices operations
>> to vendor driver for mediated devices.
>>
>> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
>> Signed-off-by: Neo Jia <cjia@nvidia.com>
>> Reviewed-by: Jike Song <jike.song@intel.com>
>>
>> Change-Id: I583f4734752971d3d112324d69e2508c88f359ec
>> ---
>>  drivers/vfio/mdev/Kconfig     |   7 ++
>>  drivers/vfio/mdev/Makefile    |   1 +
>>  drivers/vfio/mdev/mdev_core.c |  16 ++++-
>>  drivers/vfio/mdev/vfio_mdev.c | 148 ++++++++++++++++++++++++++++++++++++++++++
>>  4 files changed, 171 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/vfio/mdev/vfio_mdev.c
>>
>> diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
>> index 258481d65ebd..1aa0391d74f2 100644
>> --- a/drivers/vfio/mdev/Kconfig
>> +++ b/drivers/vfio/mdev/Kconfig
>> @@ -7,3 +7,10 @@ config VFIO_MDEV
>>  	  Provides a framework to virtualize devices.
>>
>>  	  If you don't know what do here, say N.
>> +
>> +config VFIO_MDEV_DEVICE
>> +	tristate "VFIO support for Mediated devices"
>                                    ^^^^^^^^^^^^^^^^
> 
>> +	depends on VFIO && VFIO_MDEV
>> +	default n
>> +	help
>> +	  VFIO based driver for mediated devices.
>                                 ^^^^^^^^^^^^^^^^
> nit:
> s/mediated/Mediated/
> 
> I saw in many places you use the term "Mediated device", so I guess this
> is what you preferred to name them.
> 
>> diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
>> index 31bc04801d94..fa2d5ea466ee 100644
>> --- a/drivers/vfio/mdev/Makefile
>> +++ b/drivers/vfio/mdev/Makefile
>> @@ -2,3 +2,4 @@
>>  mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
>>
>>  obj-$(CONFIG_VFIO_MDEV) += mdev.o
>> +obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
>> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
>> index 613e8a8a3b2a..1e0714ebc56a 100644
>> --- a/drivers/vfio/mdev/mdev_core.c
>> +++ b/drivers/vfio/mdev/mdev_core.c
>> @@ -354,7 +354,21 @@ int mdev_device_remove(struct device *dev, bool force_remove)
>>
>>  static int __init mdev_init(void)
>>  {
>> -	return mdev_bus_register();
>> +	int ret;
>> +
>> +	ret = mdev_bus_register();
>> +	if (ret) {
>> +		pr_err("Failed to register mdev bus\n");
> If you want to report an error message here, you should do it in a
> previous patch where you introduce the call for mdev_bus_register.
> 

Removing this error message.

>> +		return ret;
>> +	}
>> +
>> +	/*
>> +	 * Attempt to load known vfio_mdev.  This gives us a working environment
>> +	 * without the user needing to explicitly load vfio_mdev driver.
>> +	 */
>> +	request_module_nowait("vfio_mdev");
>> +
>> +	return ret;
>>  }
>>
>>  static void __exit mdev_exit(void)
> [...]
> 
> Please:
> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
> 

Thanks.

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diff mbox

Patch

diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
index 258481d65ebd..1aa0391d74f2 100644
--- a/drivers/vfio/mdev/Kconfig
+++ b/drivers/vfio/mdev/Kconfig
@@ -7,3 +7,10 @@  config VFIO_MDEV
 	  Provides a framework to virtualize devices.
 
 	  If you don't know what do here, say N.
+
+config VFIO_MDEV_DEVICE
+	tristate "VFIO support for Mediated devices"
+	depends on VFIO && VFIO_MDEV
+	default n
+	help
+	  VFIO based driver for mediated devices.
diff --git a/drivers/vfio/mdev/Makefile b/drivers/vfio/mdev/Makefile
index 31bc04801d94..fa2d5ea466ee 100644
--- a/drivers/vfio/mdev/Makefile
+++ b/drivers/vfio/mdev/Makefile
@@ -2,3 +2,4 @@ 
 mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
 
 obj-$(CONFIG_VFIO_MDEV) += mdev.o
+obj-$(CONFIG_VFIO_MDEV_DEVICE) += vfio_mdev.o
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
index 613e8a8a3b2a..1e0714ebc56a 100644
--- a/drivers/vfio/mdev/mdev_core.c
+++ b/drivers/vfio/mdev/mdev_core.c
@@ -354,7 +354,21 @@  int mdev_device_remove(struct device *dev, bool force_remove)
 
 static int __init mdev_init(void)
 {
-	return mdev_bus_register();
+	int ret;
+
+	ret = mdev_bus_register();
+	if (ret) {
+		pr_err("Failed to register mdev bus\n");
+		return ret;
+	}
+
+	/*
+	 * Attempt to load known vfio_mdev.  This gives us a working environment
+	 * without the user needing to explicitly load vfio_mdev driver.
+	 */
+	request_module_nowait("vfio_mdev");
+
+	return ret;
 }
 
 static void __exit mdev_exit(void)
diff --git a/drivers/vfio/mdev/vfio_mdev.c b/drivers/vfio/mdev/vfio_mdev.c
new file mode 100644
index 000000000000..ffc36758cb84
--- /dev/null
+++ b/drivers/vfio/mdev/vfio_mdev.c
@@ -0,0 +1,148 @@ 
+/*
+ * VFIO based driver for Mediated device
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ *     Author: Neo Jia <cjia@nvidia.com>
+ *             Kirti Wankhede <kwankhede@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vfio.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION  "0.1"
+#define DRIVER_AUTHOR   "NVIDIA Corporation"
+#define DRIVER_DESC     "VFIO based driver for Mediated device"
+
+static int vfio_mdev_open(void *device_data)
+{
+	struct mdev_device *mdev = device_data;
+	struct parent_device *parent = mdev->parent;
+	int ret;
+
+	if (unlikely(!parent->ops->open))
+		return -EINVAL;
+
+	if (!try_module_get(THIS_MODULE))
+		return -ENODEV;
+
+	ret = parent->ops->open(mdev);
+	if (ret)
+		module_put(THIS_MODULE);
+
+	return ret;
+}
+
+static void vfio_mdev_release(void *device_data)
+{
+	struct mdev_device *mdev = device_data;
+	struct parent_device *parent = mdev->parent;
+
+	if (likely(parent->ops->release))
+		parent->ops->release(mdev);
+
+	module_put(THIS_MODULE);
+}
+
+static long vfio_mdev_unlocked_ioctl(void *device_data,
+				     unsigned int cmd, unsigned long arg)
+{
+	struct mdev_device *mdev = device_data;
+	struct parent_device *parent = mdev->parent;
+
+	if (unlikely(!parent->ops->ioctl))
+		return -EINVAL;
+
+	return parent->ops->ioctl(mdev, cmd, arg);
+}
+
+static ssize_t vfio_mdev_read(void *device_data, char __user *buf,
+			      size_t count, loff_t *ppos)
+{
+	struct mdev_device *mdev = device_data;
+	struct parent_device *parent = mdev->parent;
+
+	if (unlikely(!parent->ops->read))
+		return -EINVAL;
+
+	return parent->ops->read(mdev, buf, count, ppos);
+}
+
+static ssize_t vfio_mdev_write(void *device_data, const char __user *buf,
+			       size_t count, loff_t *ppos)
+{
+	struct mdev_device *mdev = device_data;
+	struct parent_device *parent = mdev->parent;
+
+	if (unlikely(!parent->ops->write))
+		return -EINVAL;
+
+	return parent->ops->write(mdev, buf, count, ppos);
+}
+
+static int vfio_mdev_mmap(void *device_data, struct vm_area_struct *vma)
+{
+	struct mdev_device *mdev = device_data;
+	struct parent_device *parent = mdev->parent;
+
+	if (unlikely(!parent->ops->mmap))
+		return -EINVAL;
+
+	return parent->ops->mmap(mdev, vma);
+}
+
+static const struct vfio_device_ops vfio_mdev_dev_ops = {
+	.name		= "vfio-mdev",
+	.open		= vfio_mdev_open,
+	.release	= vfio_mdev_release,
+	.ioctl		= vfio_mdev_unlocked_ioctl,
+	.read		= vfio_mdev_read,
+	.write		= vfio_mdev_write,
+	.mmap		= vfio_mdev_mmap,
+};
+
+int vfio_mdev_probe(struct device *dev)
+{
+	struct mdev_device *mdev = to_mdev_device(dev);
+
+	return vfio_add_group_dev(dev, &vfio_mdev_dev_ops, mdev);
+}
+
+void vfio_mdev_remove(struct device *dev)
+{
+	vfio_del_group_dev(dev);
+}
+
+struct mdev_driver vfio_mdev_driver = {
+	.name	= "vfio_mdev",
+	.probe	= vfio_mdev_probe,
+	.remove	= vfio_mdev_remove,
+};
+
+static int __init vfio_mdev_init(void)
+{
+	return mdev_register_driver(&vfio_mdev_driver, THIS_MODULE);
+}
+
+static void __exit vfio_mdev_exit(void)
+{
+	mdev_unregister_driver(&vfio_mdev_driver);
+}
+
+module_init(vfio_mdev_init)
+module_exit(vfio_mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);