Resguardo inicial

linux-7.2.3/drivers/vfio/mdev/Kconfig

@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config VFIO_MDEV
+	tristate

linux-7.2.3/drivers/vfio/mdev/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+mdev-y := mdev_core.o mdev_sysfs.o mdev_driver.o
+
+obj-$(CONFIG_VFIO_MDEV) += mdev.o

linux-7.2.3/drivers/vfio/mdev/mdev_core.c

@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Mediated device Core Driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ *     Author: Neo Jia <cjia@nvidia.com>
+ *             Kirti Wankhede <kwankhede@nvidia.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+#define DRIVER_VERSION		"0.1"
+#define DRIVER_AUTHOR		"NVIDIA Corporation"
+#define DRIVER_DESC		"Mediated device Core Driver"
+
+static struct class_compat *mdev_bus_compat_class;
+
+static LIST_HEAD(mdev_list);
+static DEFINE_MUTEX(mdev_list_lock);
+
+/* Caller must hold parent unreg_sem read or write lock */
+static void mdev_device_remove_common(struct mdev_device *mdev)
+{
+	struct mdev_parent *parent = mdev->type->parent;
+
+	mdev_remove_sysfs_files(mdev);
+	device_del(&mdev->dev);
+	lockdep_assert_held(&parent->unreg_sem);
+	/* Balances with device_initialize() */
+	put_device(&mdev->dev);
+}
+
+static int mdev_device_remove_cb(struct device *dev, void *data)
+{
+	if (dev->bus == &mdev_bus_type)
+		mdev_device_remove_common(to_mdev_device(dev));
+	return 0;
+}
+
+/*
+ * mdev_register_parent: Register a device as parent for mdevs
+ * @parent: parent structure registered
+ * @dev: device structure representing parent device.
+ * @mdev_driver: Device driver to bind to the newly created mdev
+ * @types: Array of supported mdev types
+ * @nr_types: Number of entries in @types
+ *
+ * Registers the @parent stucture as a parent for mdev types and thus mdev
+ * devices.  The caller needs to hold a reference on @dev that must not be
+ * released until after the call to mdev_unregister_parent().
+ *
+ * Returns a negative value on error, otherwise 0.
+ */
+int mdev_register_parent(struct mdev_parent *parent, struct device *dev,
+		struct mdev_driver *mdev_driver, struct mdev_type **types,
+		unsigned int nr_types)
+{
+	char *env_string = "MDEV_STATE=registered";
+	char *envp[] = { env_string, NULL };
+	int ret;
+
+	memset(parent, 0, sizeof(*parent));
+	init_rwsem(&parent->unreg_sem);
+	parent->dev = dev;
+	parent->mdev_driver = mdev_driver;
+	parent->types = types;
+	parent->nr_types = nr_types;
+	atomic_set(&parent->available_instances, mdev_driver->max_instances);
+
+	ret = parent_create_sysfs_files(parent);
+	if (ret)
+		return ret;
+
+	ret = class_compat_create_link(mdev_bus_compat_class, dev);
+	if (ret)
+		dev_warn(dev, "Failed to create compatibility class link\n");
+
+	dev_info(dev, "MDEV: Registered\n");
+	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
+	return 0;
+}
+EXPORT_SYMBOL(mdev_register_parent);
+
+/*
+ * mdev_unregister_parent : Unregister a parent device
+ * @parent: parent structure to unregister
+ */
+void mdev_unregister_parent(struct mdev_parent *parent)
+{
+	char *env_string = "MDEV_STATE=unregistered";
+	char *envp[] = { env_string, NULL };
+
+	dev_info(parent->dev, "MDEV: Unregistering\n");
+
+	down_write(&parent->unreg_sem);
+	class_compat_remove_link(mdev_bus_compat_class, parent->dev);
+	device_for_each_child(parent->dev, NULL, mdev_device_remove_cb);
+	parent_remove_sysfs_files(parent);
+	up_write(&parent->unreg_sem);
+
+	kobject_uevent_env(&parent->dev->kobj, KOBJ_CHANGE, envp);
+}
+EXPORT_SYMBOL(mdev_unregister_parent);
+
+static void mdev_device_release(struct device *dev)
+{
+	struct mdev_device *mdev = to_mdev_device(dev);
+	struct mdev_parent *parent = mdev->type->parent;
+
+	mutex_lock(&mdev_list_lock);
+	list_del(&mdev->next);
+	if (!parent->mdev_driver->get_available)
+		atomic_inc(&parent->available_instances);
+	mutex_unlock(&mdev_list_lock);
+
+	/* Pairs with the get in mdev_device_create() */
+	kobject_put(&mdev->type->kobj);
+
+	dev_dbg(&mdev->dev, "MDEV: destroying\n");
+	kfree(mdev);
+}
+
+int mdev_device_create(struct mdev_type *type, const guid_t *uuid)
+{
+	int ret;
+	struct mdev_device *mdev, *tmp;
+	struct mdev_parent *parent = type->parent;
+	struct mdev_driver *drv = parent->mdev_driver;
+
+	mutex_lock(&mdev_list_lock);
+
+	/* Check for duplicate */
+	list_for_each_entry(tmp, &mdev_list, next) {
+		if (guid_equal(&tmp->uuid, uuid)) {
+			mutex_unlock(&mdev_list_lock);
+			return -EEXIST;
+		}
+	}
+
+	if (!drv->get_available) {
+		/*
+		 * Note: that non-atomic read and dec is fine here because
+		 * all modifications are under mdev_list_lock.
+		 */
+		if (!atomic_read(&parent->available_instances)) {
+			mutex_unlock(&mdev_list_lock);
+			return -EUSERS;
+		}
+		atomic_dec(&parent->available_instances);
+	}
+
+	mdev = kzalloc_obj(*mdev);
+	if (!mdev) {
+		mutex_unlock(&mdev_list_lock);
+		return -ENOMEM;
+	}
+
+	device_initialize(&mdev->dev);
+	mdev->dev.parent  = parent->dev;
+	mdev->dev.bus = &mdev_bus_type;
+	mdev->dev.release = mdev_device_release;
+	mdev->dev.groups = mdev_device_groups;
+	mdev->type = type;
+	/* Pairs with the put in mdev_device_release() */
+	kobject_get(&type->kobj);
+
+	guid_copy(&mdev->uuid, uuid);
+	list_add(&mdev->next, &mdev_list);
+	mutex_unlock(&mdev_list_lock);
+
+	ret = dev_set_name(&mdev->dev, "%pUl", uuid);
+	if (ret)
+		goto out_put_device;
+
+	/* Check if parent unregistration has started */
+	if (!down_read_trylock(&parent->unreg_sem)) {
+		ret = -ENODEV;
+		goto out_put_device;
+	}
+
+	ret = device_add(&mdev->dev);
+	if (ret)
+		goto out_unlock;
+
+	ret = device_driver_attach(&drv->driver, &mdev->dev);
+	if (ret)
+		goto out_del;
+
+	ret = mdev_create_sysfs_files(mdev);
+	if (ret)
+		goto out_del;
+
+	mdev->active = true;
+	dev_dbg(&mdev->dev, "MDEV: created\n");
+	up_read(&parent->unreg_sem);
+
+	return 0;
+
+out_del:
+	device_del(&mdev->dev);
+out_unlock:
+	up_read(&parent->unreg_sem);
+out_put_device:
+	put_device(&mdev->dev);
+	return ret;
+}
+
+int mdev_device_remove(struct mdev_device *mdev)
+{
+	struct mdev_device *tmp;
+	struct mdev_parent *parent = mdev->type->parent;
+
+	mutex_lock(&mdev_list_lock);
+	list_for_each_entry(tmp, &mdev_list, next) {
+		if (tmp == mdev)
+			break;
+	}
+
+	if (tmp != mdev) {
+		mutex_unlock(&mdev_list_lock);
+		return -ENODEV;
+	}
+
+	if (!mdev->active) {
+		mutex_unlock(&mdev_list_lock);
+		return -EAGAIN;
+	}
+
+	mdev->active = false;
+	mutex_unlock(&mdev_list_lock);
+
+	/* Check if parent unregistration has started */
+	if (!down_read_trylock(&parent->unreg_sem))
+		return -ENODEV;
+
+	mdev_device_remove_common(mdev);
+	up_read(&parent->unreg_sem);
+	return 0;
+}
+
+static int __init mdev_init(void)
+{
+	int ret;
+
+	ret = bus_register(&mdev_bus_type);
+	if (ret)
+		return ret;
+
+	mdev_bus_compat_class = class_compat_register("mdev_bus");
+	if (!mdev_bus_compat_class) {
+		bus_unregister(&mdev_bus_type);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void __exit mdev_exit(void)
+{
+	class_compat_unregister(mdev_bus_compat_class);
+	bus_unregister(&mdev_bus_type);
+}
+
+subsys_initcall(mdev_init)
+module_exit(mdev_exit)
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);

linux-7.2.3/drivers/vfio/mdev/mdev_driver.c

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MDEV driver
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ *     Author: Neo Jia <cjia@nvidia.com>
+ *             Kirti Wankhede <kwankhede@nvidia.com>
+ */
+
+#include <linux/iommu.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+static int mdev_probe(struct device *dev)
+{
+	struct mdev_driver *drv =
+		container_of(dev->driver, struct mdev_driver, driver);
+
+	if (!drv->probe)
+		return 0;
+	return drv->probe(to_mdev_device(dev));
+}
+
+static void mdev_remove(struct device *dev)
+{
+	struct mdev_driver *drv =
+		container_of(dev->driver, struct mdev_driver, driver);
+
+	if (drv->remove)
+		drv->remove(to_mdev_device(dev));
+}
+
+static int mdev_match(struct device *dev, const struct device_driver *drv)
+{
+	/*
+	 * No drivers automatically match. Drivers are only bound by explicit
+	 * device_driver_attach()
+	 */
+	return 0;
+}
+
+const struct bus_type mdev_bus_type = {
+	.name		= "mdev",
+	.probe		= mdev_probe,
+	.remove		= mdev_remove,
+	.match		= mdev_match,
+};
+
+/**
+ * mdev_register_driver - register a new MDEV driver
+ * @drv: the driver to register
+ *
+ * Returns a negative value on error, otherwise 0.
+ **/
+int mdev_register_driver(struct mdev_driver *drv)
+{
+	if (!drv->device_api)
+		return -EINVAL;
+
+	/* initialize common driver fields */
+	drv->driver.bus = &mdev_bus_type;
+	return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL(mdev_register_driver);
+
+/*
+ * mdev_unregister_driver - unregister MDEV driver
+ * @drv: the driver to unregister
+ */
+void mdev_unregister_driver(struct mdev_driver *drv)
+{
+	driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL(mdev_unregister_driver);

linux-7.2.3/drivers/vfio/mdev/mdev_private.h

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Mediated device internal definitions
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ *     Author: Neo Jia <cjia@nvidia.com>
+ *             Kirti Wankhede <kwankhede@nvidia.com>
+ */
+
+#ifndef MDEV_PRIVATE_H
+#define MDEV_PRIVATE_H
+
+extern const struct bus_type mdev_bus_type;
+extern const struct attribute_group *mdev_device_groups[];
+
+#define to_mdev_type_attr(_attr)	\
+	container_of(_attr, struct mdev_type_attribute, attr)
+#define to_mdev_type(_kobj)		\
+	container_of(_kobj, struct mdev_type, kobj)
+
+int  parent_create_sysfs_files(struct mdev_parent *parent);
+void parent_remove_sysfs_files(struct mdev_parent *parent);
+
+int  mdev_create_sysfs_files(struct mdev_device *mdev);
+void mdev_remove_sysfs_files(struct mdev_device *mdev);
+
+int mdev_device_create(struct mdev_type *kobj, const guid_t *uuid);
+int  mdev_device_remove(struct mdev_device *dev);
+
+#endif /* MDEV_PRIVATE_H */

linux-7.2.3/drivers/vfio/mdev/mdev_sysfs.c

@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * File attributes for Mediated devices
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ *     Author: Neo Jia <cjia@nvidia.com>
+ *             Kirti Wankhede <kwankhede@nvidia.com>
+ */
+
+#include <linux/sysfs.h>
+#include <linux/ctype.h>
+#include <linux/slab.h>
+#include <linux/mdev.h>
+
+#include "mdev_private.h"
+
+struct mdev_type_attribute {
+	struct attribute attr;
+	ssize_t (*show)(struct mdev_type *mtype,
+			struct mdev_type_attribute *attr, char *buf);
+	ssize_t (*store)(struct mdev_type *mtype,
+			 struct mdev_type_attribute *attr, const char *buf,
+			 size_t count);
+};
+
+#define MDEV_TYPE_ATTR_RO(_name) \
+	struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
+#define MDEV_TYPE_ATTR_WO(_name) \
+	struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
+
+static ssize_t mdev_type_attr_show(struct kobject *kobj,
+				     struct attribute *__attr, char *buf)
+{
+	struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
+	struct mdev_type *type = to_mdev_type(kobj);
+	ssize_t ret = -EIO;
+
+	if (attr->show)
+		ret = attr->show(type, attr, buf);
+	return ret;
+}
+
+static ssize_t mdev_type_attr_store(struct kobject *kobj,
+				      struct attribute *__attr,
+				      const char *buf, size_t count)
+{
+	struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
+	struct mdev_type *type = to_mdev_type(kobj);
+	ssize_t ret = -EIO;
+
+	if (attr->store)
+		ret = attr->store(type, attr, buf, count);
+	return ret;
+}
+
+static const struct sysfs_ops mdev_type_sysfs_ops = {
+	.show = mdev_type_attr_show,
+	.store = mdev_type_attr_store,
+};
+
+static ssize_t create_store(struct mdev_type *mtype,
+			    struct mdev_type_attribute *attr, const char *buf,
+			    size_t count)
+{
+	char *str;
+	guid_t uuid;
+	int ret;
+
+	if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1))
+		return -EINVAL;
+
+	str = kstrndup(buf, count, GFP_KERNEL);
+	if (!str)
+		return -ENOMEM;
+
+	ret = guid_parse(str, &uuid);
+	kfree(str);
+	if (ret)
+		return ret;
+
+	ret = mdev_device_create(mtype, &uuid);
+	if (ret)
+		return ret;
+
+	return count;
+}
+static MDEV_TYPE_ATTR_WO(create);
+
+static ssize_t device_api_show(struct mdev_type *mtype,
+			       struct mdev_type_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%s\n", mtype->parent->mdev_driver->device_api);
+}
+static MDEV_TYPE_ATTR_RO(device_api);
+
+static ssize_t name_show(struct mdev_type *mtype,
+			 struct mdev_type_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "%s\n",
+		mtype->pretty_name ? mtype->pretty_name : mtype->sysfs_name);
+}
+
+static MDEV_TYPE_ATTR_RO(name);
+
+static ssize_t available_instances_show(struct mdev_type *mtype,
+					struct mdev_type_attribute *attr,
+					char *buf)
+{
+	struct mdev_driver *drv = mtype->parent->mdev_driver;
+
+	if (drv->get_available)
+		return sysfs_emit(buf, "%u\n", drv->get_available(mtype));
+	return sysfs_emit(buf, "%u\n",
+			  atomic_read(&mtype->parent->available_instances));
+}
+static MDEV_TYPE_ATTR_RO(available_instances);
+
+static ssize_t description_show(struct mdev_type *mtype,
+				struct mdev_type_attribute *attr,
+				char *buf)
+{
+	return mtype->parent->mdev_driver->show_description(mtype, buf);
+}
+static MDEV_TYPE_ATTR_RO(description);
+
+static struct attribute *mdev_types_core_attrs[] = {
+	&mdev_type_attr_create.attr,
+	&mdev_type_attr_device_api.attr,
+	&mdev_type_attr_name.attr,
+	&mdev_type_attr_available_instances.attr,
+	&mdev_type_attr_description.attr,
+	NULL,
+};
+
+static umode_t mdev_types_core_is_visible(struct kobject *kobj,
+					  struct attribute *attr, int n)
+{
+	if (attr == &mdev_type_attr_description.attr &&
+	    !to_mdev_type(kobj)->parent->mdev_driver->show_description)
+		return 0;
+	return attr->mode;
+}
+
+static struct attribute_group mdev_type_core_group = {
+	.attrs = mdev_types_core_attrs,
+	.is_visible = mdev_types_core_is_visible,
+};
+
+static const struct attribute_group *mdev_type_groups[] = {
+	&mdev_type_core_group,
+	NULL,
+};
+
+static void mdev_type_release(struct kobject *kobj)
+{
+	struct mdev_type *type = to_mdev_type(kobj);
+
+	pr_debug("Releasing group %s\n", kobj->name);
+	/* Pairs with the get in mdev_type_add() */
+	put_device(type->parent->dev);
+}
+
+static const struct kobj_type mdev_type_ktype = {
+	.sysfs_ops	= &mdev_type_sysfs_ops,
+	.release	= mdev_type_release,
+	.default_groups	= mdev_type_groups,
+};
+
+static int mdev_type_add(struct mdev_parent *parent, struct mdev_type *type)
+{
+	int ret;
+
+	type->kobj.kset = parent->mdev_types_kset;
+	type->parent = parent;
+	/* Pairs with the put in mdev_type_release() */
+	get_device(parent->dev);
+
+	ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
+				   "%s-%s", dev_driver_string(parent->dev),
+				   type->sysfs_name);
+	if (ret) {
+		kobject_put(&type->kobj);
+		return ret;
+	}
+
+	type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
+	if (!type->devices_kobj) {
+		ret = -ENOMEM;
+		goto attr_devices_failed;
+	}
+
+	return 0;
+
+attr_devices_failed:
+	kobject_del(&type->kobj);
+	kobject_put(&type->kobj);
+	return ret;
+}
+
+static void mdev_type_remove(struct mdev_type *type)
+{
+	kobject_put(type->devices_kobj);
+	kobject_del(&type->kobj);
+	kobject_put(&type->kobj);
+}
+
+/* mdev sysfs functions */
+void parent_remove_sysfs_files(struct mdev_parent *parent)
+{
+	int i;
+
+	for (i = 0; i < parent->nr_types; i++)
+		mdev_type_remove(parent->types[i]);
+	kset_unregister(parent->mdev_types_kset);
+}
+
+int parent_create_sysfs_files(struct mdev_parent *parent)
+{
+	int ret, i;
+
+	parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",
+					       NULL, &parent->dev->kobj);
+	if (!parent->mdev_types_kset)
+		return -ENOMEM;
+
+	for (i = 0; i < parent->nr_types; i++) {
+		ret = mdev_type_add(parent, parent->types[i]);
+		if (ret)
+			goto out_err;
+	}
+	return 0;
+
+out_err:
+	while (--i >= 0)
+		mdev_type_remove(parent->types[i]);
+	kset_unregister(parent->mdev_types_kset);
+	return ret;
+}
+
+static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
+{
+	struct mdev_device *mdev = to_mdev_device(dev);
+	unsigned long val;
+
+	if (kstrtoul(buf, 0, &val) < 0)
+		return -EINVAL;
+
+	if (val && device_remove_file_self(dev, attr)) {
+		int ret;
+
+		ret = mdev_device_remove(mdev);
+		if (ret)
+			return ret;
+	}
+
+	return count;
+}
+
+static DEVICE_ATTR_WO(remove);
+
+static struct attribute *mdev_device_attrs[] = {
+	&dev_attr_remove.attr,
+	NULL,
+};
+
+static const struct attribute_group mdev_device_group = {
+	.attrs = mdev_device_attrs,
+};
+
+const struct attribute_group *mdev_device_groups[] = {
+	&mdev_device_group,
+	NULL
+};
+
+int mdev_create_sysfs_files(struct mdev_device *mdev)
+{
+	struct mdev_type *type = mdev->type;
+	struct kobject *kobj = &mdev->dev.kobj;
+	int ret;
+
+	ret = sysfs_create_link(type->devices_kobj, kobj, dev_name(&mdev->dev));
+	if (ret)
+		return ret;
+
+	ret = sysfs_create_link(kobj, &type->kobj, "mdev_type");
+	if (ret)
+		goto type_link_failed;
+	return ret;
+
+type_link_failed:
+	sysfs_remove_link(mdev->type->devices_kobj, dev_name(&mdev->dev));
+	return ret;
+}
+
+void mdev_remove_sysfs_files(struct mdev_device *mdev)
+{
+	struct kobject *kobj = &mdev->dev.kobj;
+
+	sysfs_remove_link(kobj, "mdev_type");
+	sysfs_remove_link(mdev->type->devices_kobj, dev_name(&mdev->dev));
+}