uio: Statically allocate uio_class and use class .dev_attrs.

Instead of adding uio class attributes manually after the uio device has
been created and we have sent a uevent to userspace, use the class
attribute mechanism.  This removes races and makes the code simpler.

At the same time don't bother to dynamically allocate a struct class for
uio, just declare one statically.  Less code is needed and it is easier
to set the class parameters.tune the class

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hans J. Koch <hjk@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Eric W. Biederman 2010-09-14 11:38:36 -07:00 committed by Greg Kroah-Hartman
parent 91960a46c6
commit c66fdab64f

View File

@ -46,9 +46,6 @@ static struct cdev *uio_cdev;
static DEFINE_IDR(uio_idr);
static const struct file_operations uio_fops;
/* UIO class infrastructure */
static struct class *uio_class;
/* Protect idr accesses */
static DEFINE_MUTEX(minor_lock);
@ -233,7 +230,6 @@ static ssize_t show_name(struct device *dev,
struct uio_device *idev = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", idev->info->name);
}
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
static ssize_t show_version(struct device *dev,
struct device_attribute *attr, char *buf)
@ -241,7 +237,6 @@ static ssize_t show_version(struct device *dev,
struct uio_device *idev = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", idev->info->version);
}
static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
static ssize_t show_event(struct device *dev,
struct device_attribute *attr, char *buf)
@ -249,17 +244,18 @@ static ssize_t show_event(struct device *dev,
struct uio_device *idev = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", (unsigned int)atomic_read(&idev->event));
}
static DEVICE_ATTR(event, S_IRUGO, show_event, NULL);
static struct attribute *uio_attrs[] = {
&dev_attr_name.attr,
&dev_attr_version.attr,
&dev_attr_event.attr,
NULL,
static struct device_attribute uio_class_attributes[] = {
__ATTR(name, S_IRUGO, show_name, NULL),
__ATTR(version, S_IRUGO, show_version, NULL),
__ATTR(event, S_IRUGO, show_event, NULL),
{}
};
static struct attribute_group uio_attr_grp = {
.attrs = uio_attrs,
/* UIO class infrastructure */
static struct class uio_class = {
.name = "uio",
.dev_attrs = uio_class_attributes,
};
/*
@ -276,10 +272,6 @@ static int uio_dev_add_attributes(struct uio_device *idev)
struct uio_port *port;
struct uio_portio *portio;
ret = sysfs_create_group(&idev->dev->kobj, &uio_attr_grp);
if (ret)
goto err_group;
for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
mem = &idev->info->mem[mi];
if (mem->size == 0)
@ -347,8 +339,6 @@ err_map:
kobject_put(&map->kobj);
}
kobject_put(idev->map_dir);
sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
err_group:
dev_err(idev->dev, "error creating sysfs files (%d)\n", ret);
return ret;
}
@ -374,8 +364,6 @@ static void uio_dev_del_attributes(struct uio_device *idev)
kobject_put(&port->portio->kobj);
}
kobject_put(idev->portio_dir);
sysfs_remove_group(&idev->dev->kobj, &uio_attr_grp);
}
static int uio_get_minor(struct uio_device *idev)
@ -775,7 +763,6 @@ static void uio_major_cleanup(void)
static int init_uio_class(void)
{
struct class *class;
int ret;
/* This is the first time in here, set everything up properly */
@ -783,16 +770,14 @@ static int init_uio_class(void)
if (ret)
goto exit;
class = class_create(THIS_MODULE, "uio");
if (IS_ERR(class)) {
ret = IS_ERR(class);
printk(KERN_ERR "class_create failed for uio\n");
goto err_class_create;
ret = class_register(&uio_class);
if (ret) {
printk(KERN_ERR "class_register failed for uio\n");
goto err_class_register;
}
uio_class = class;
return 0;
err_class_create:
err_class_register:
uio_major_cleanup();
exit:
return ret;
@ -800,9 +785,7 @@ exit:
static void release_uio_class(void)
{
/* Ok, we cheat as we know we only have one uio_class */
class_destroy(uio_class);
uio_class = NULL;
class_unregister(&uio_class);
uio_major_cleanup();
}
@ -841,7 +824,7 @@ int __uio_register_device(struct module *owner,
if (ret)
goto err_get_minor;
idev->dev = device_create(uio_class, parent,
idev->dev = device_create(&uio_class, parent,
MKDEV(uio_major, idev->minor), idev,
"uio%d", idev->minor);
if (IS_ERR(idev->dev)) {
@ -868,7 +851,7 @@ int __uio_register_device(struct module *owner,
err_request_irq:
uio_dev_del_attributes(idev);
err_uio_dev_add_attributes:
device_destroy(uio_class, MKDEV(uio_major, idev->minor));
device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
err_device_create:
uio_free_minor(idev);
err_get_minor:
@ -899,7 +882,7 @@ void uio_unregister_device(struct uio_info *info)
uio_dev_del_attributes(idev);
device_destroy(uio_class, MKDEV(uio_major, idev->minor));
device_destroy(&uio_class, MKDEV(uio_major, idev->minor));
kfree(idev);
return;