linuxdebug/drivers/vfio/mdev/mdev_sysfs.c

302 lines
7.0 KiB
C

// 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 sprintf(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 add_mdev_supported_type() */
put_device(type->parent->dev);
}
static 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]);
return 0;
}
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));
}