mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-28 20:02:17 +00:00
9c799c224d
Many of the mdev drivers use a simple counter for keeping track of the available instances. Move this code to the core code and store the counter in the mdev_parent. Implement it using correct locking, fixing mdpy. Drivers just provide the value in the mdev_driver at registration time and the core code takes care of maintaining it and exposing the value in sysfs. [hch: count instances per-parent instead of per-type, use an atomic_t to avoid taking mdev_list_lock in the show method] Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Link: https://lore.kernel.org/r/20220923092652.100656-15-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
89 lines
2.4 KiB
C
89 lines
2.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* Mediated device definition
|
|
*
|
|
* Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
|
|
* Author: Neo Jia <cjia@nvidia.com>
|
|
* Kirti Wankhede <kwankhede@nvidia.com>
|
|
*/
|
|
|
|
#ifndef MDEV_H
|
|
#define MDEV_H
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/uuid.h>
|
|
|
|
struct mdev_type;
|
|
|
|
struct mdev_device {
|
|
struct device dev;
|
|
guid_t uuid;
|
|
struct list_head next;
|
|
struct mdev_type *type;
|
|
bool active;
|
|
};
|
|
|
|
struct mdev_type {
|
|
/* set by the driver before calling mdev_register parent: */
|
|
const char *sysfs_name;
|
|
const char *pretty_name;
|
|
|
|
/* set by the core, can be used drivers */
|
|
struct mdev_parent *parent;
|
|
|
|
/* internal only */
|
|
struct kobject kobj;
|
|
struct kobject *devices_kobj;
|
|
};
|
|
|
|
/* embedded into the struct device that the mdev devices hang off */
|
|
struct mdev_parent {
|
|
struct device *dev;
|
|
struct mdev_driver *mdev_driver;
|
|
struct kset *mdev_types_kset;
|
|
/* Synchronize device creation/removal with parent unregistration */
|
|
struct rw_semaphore unreg_sem;
|
|
struct mdev_type **types;
|
|
unsigned int nr_types;
|
|
atomic_t available_instances;
|
|
};
|
|
|
|
static inline struct mdev_device *to_mdev_device(struct device *dev)
|
|
{
|
|
return container_of(dev, struct mdev_device, dev);
|
|
}
|
|
|
|
/**
|
|
* struct mdev_driver - Mediated device driver
|
|
* @device_api: string to return for the device_api sysfs
|
|
* @max_instances: maximum number of instances supported (optional)
|
|
* @probe: called when new device created
|
|
* @remove: called when device removed
|
|
* @get_available: Return the max number of instances that can be created
|
|
* @show_description: Print a description of the mtype
|
|
* @driver: device driver structure
|
|
**/
|
|
struct mdev_driver {
|
|
const char *device_api;
|
|
unsigned int max_instances;
|
|
int (*probe)(struct mdev_device *dev);
|
|
void (*remove)(struct mdev_device *dev);
|
|
unsigned int (*get_available)(struct mdev_type *mtype);
|
|
ssize_t (*show_description)(struct mdev_type *mtype, char *buf);
|
|
struct device_driver 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);
|
|
void mdev_unregister_parent(struct mdev_parent *parent);
|
|
|
|
int mdev_register_driver(struct mdev_driver *drv);
|
|
void mdev_unregister_driver(struct mdev_driver *drv);
|
|
|
|
static inline struct device *mdev_dev(struct mdev_device *mdev)
|
|
{
|
|
return &mdev->dev;
|
|
}
|
|
|
|
#endif /* MDEV_H */
|