diff options
Diffstat (limited to 'drivers/vfio/mdev/mdev_core.c')
-rw-r--r-- | drivers/vfio/mdev/mdev_core.c | 195 |
1 files changed, 48 insertions, 147 deletions
diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c index b8b9e7911e55..58f91b3bd670 100644 --- a/drivers/vfio/mdev/mdev_core.c +++ b/drivers/vfio/mdev/mdev_core.c @@ -8,9 +8,7 @@ */ #include <linux/module.h> -#include <linux/device.h> #include <linux/slab.h> -#include <linux/uuid.h> #include <linux/sysfs.h> #include <linux/mdev.h> @@ -20,71 +18,11 @@ #define DRIVER_AUTHOR "NVIDIA Corporation" #define DRIVER_DESC "Mediated device Core Driver" -static LIST_HEAD(parent_list); -static DEFINE_MUTEX(parent_list_lock); static struct class_compat *mdev_bus_compat_class; static LIST_HEAD(mdev_list); static DEFINE_MUTEX(mdev_list_lock); -struct device *mdev_parent_dev(struct mdev_device *mdev) -{ - return mdev->type->parent->dev; -} -EXPORT_SYMBOL(mdev_parent_dev); - -/* - * Return the index in supported_type_groups that this mdev_device was created - * from. - */ -unsigned int mdev_get_type_group_id(struct mdev_device *mdev) -{ - return mdev->type->type_group_id; -} -EXPORT_SYMBOL(mdev_get_type_group_id); - -/* - * Used in mdev_type_attribute sysfs functions to return the index in the - * supported_type_groups that the sysfs is called from. - */ -unsigned int mtype_get_type_group_id(struct mdev_type *mtype) -{ - return mtype->type_group_id; -} -EXPORT_SYMBOL(mtype_get_type_group_id); - -/* - * Used in mdev_type_attribute sysfs functions to return the parent struct - * device - */ -struct device *mtype_get_parent_dev(struct mdev_type *mtype) -{ - return mtype->parent->dev; -} -EXPORT_SYMBOL(mtype_get_parent_dev); - -/* Should be called holding parent_list_lock */ -static struct mdev_parent *__find_parent_device(struct device *dev) -{ - struct mdev_parent *parent; - - list_for_each_entry(parent, &parent_list, next) { - if (parent->dev == dev) - return parent; - } - return NULL; -} - -void mdev_release_parent(struct kref *kref) -{ - struct mdev_parent *parent = container_of(kref, struct mdev_parent, - ref); - struct device *dev = parent->dev; - - kfree(parent); - put_device(dev); -} - /* Caller must hold parent unreg_sem read or write lock */ static void mdev_device_remove_common(struct mdev_device *mdev) { @@ -99,145 +37,96 @@ static void mdev_device_remove_common(struct mdev_device *mdev) static int mdev_device_remove_cb(struct device *dev, void *data) { - struct mdev_device *mdev = mdev_from_dev(dev); - - if (mdev) - mdev_device_remove_common(mdev); + if (dev->bus == &mdev_bus_type) + mdev_device_remove_common(to_mdev_device(dev)); return 0; } /* - * mdev_register_device : Register a device + * 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(). * - * Add device to list of registered parent devices. * Returns a negative value on error, otherwise 0. */ -int mdev_register_device(struct device *dev, struct mdev_driver *mdev_driver) +int mdev_register_parent(struct mdev_parent *parent, struct device *dev, + struct mdev_driver *mdev_driver, struct mdev_type **types, + unsigned int nr_types) { - int ret; - struct mdev_parent *parent; char *env_string = "MDEV_STATE=registered"; char *envp[] = { env_string, NULL }; + int ret; - /* check for mandatory ops */ - if (!mdev_driver->supported_type_groups) - return -EINVAL; - - dev = get_device(dev); - if (!dev) - return -EINVAL; - - mutex_lock(&parent_list_lock); - - /* Check for duplicate */ - parent = __find_parent_device(dev); - if (parent) { - parent = NULL; - ret = -EEXIST; - goto add_dev_err; - } - - parent = kzalloc(sizeof(*parent), GFP_KERNEL); - if (!parent) { - ret = -ENOMEM; - goto add_dev_err; - } - - kref_init(&parent->ref); + 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); if (!mdev_bus_compat_class) { mdev_bus_compat_class = class_compat_register("mdev_bus"); - if (!mdev_bus_compat_class) { - ret = -ENOMEM; - goto add_dev_err; - } + if (!mdev_bus_compat_class) + return -ENOMEM; } ret = parent_create_sysfs_files(parent); if (ret) - goto add_dev_err; + return ret; ret = class_compat_create_link(mdev_bus_compat_class, dev, NULL); if (ret) dev_warn(dev, "Failed to create compatibility class link\n"); - list_add(&parent->next, &parent_list); - mutex_unlock(&parent_list_lock); - dev_info(dev, "MDEV: Registered\n"); kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); - return 0; - -add_dev_err: - mutex_unlock(&parent_list_lock); - if (parent) - mdev_put_parent(parent); - else - put_device(dev); - return ret; } -EXPORT_SYMBOL(mdev_register_device); +EXPORT_SYMBOL(mdev_register_parent); /* - * mdev_unregister_device : Unregister a parent device - * @dev: device structure representing parent device. - * - * Remove device from list of registered parent devices. Give a chance to free - * existing mediated devices for given device. + * mdev_unregister_parent : Unregister a parent device + * @parent: parent structure to unregister */ - -void mdev_unregister_device(struct device *dev) +void mdev_unregister_parent(struct mdev_parent *parent) { - struct mdev_parent *parent; char *env_string = "MDEV_STATE=unregistered"; char *envp[] = { env_string, NULL }; - mutex_lock(&parent_list_lock); - parent = __find_parent_device(dev); - - if (!parent) { - mutex_unlock(&parent_list_lock); - return; - } - dev_info(dev, "MDEV: Unregistering\n"); - - list_del(&parent->next); - mutex_unlock(&parent_list_lock); + dev_info(parent->dev, "MDEV: Unregistering\n"); down_write(&parent->unreg_sem); - - class_compat_remove_link(mdev_bus_compat_class, dev, NULL); - - device_for_each_child(dev, NULL, mdev_device_remove_cb); - + class_compat_remove_link(mdev_bus_compat_class, parent->dev, NULL); + device_for_each_child(parent->dev, NULL, mdev_device_remove_cb); parent_remove_sysfs_files(parent); up_write(&parent->unreg_sem); - mdev_put_parent(parent); - - /* We still have the caller's reference to use for the uevent */ - kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); + kobject_uevent_env(&parent->dev->kobj, KOBJ_CHANGE, envp); } -EXPORT_SYMBOL(mdev_unregister_device); +EXPORT_SYMBOL(mdev_unregister_parent); static void mdev_device_release(struct device *dev) { struct mdev_device *mdev = to_mdev_device(dev); - - /* Pairs with the get in mdev_device_create() */ - kobject_put(&mdev->type->kobj); + 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); } @@ -259,6 +148,18 @@ int mdev_device_create(struct mdev_type *type, const guid_t *uuid) } } + 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(sizeof(*mdev), GFP_KERNEL); if (!mdev) { mutex_unlock(&mdev_list_lock); |