Re: [patch] convert the scsi layer to use struct device

James Bottomley
2008-03-15T18:01:44Z

On Sat, 2008-03-15 at 11:16 -0500, James Bottomley wrote:
> On Sat, 2008-03-15 at 16:17 +0100, Kay Sievers wrote:
> > We just need to create something like a "contains" link from the
> > component to the scsi device, and a "enclosure" link at the scsi device
> > back to the component, right?
>
> Assuming you're moving to the single tree model, then I can easily do
> this:
>
> <real enclosure device>/<enclosure>/<enclosure component>/device -> link
> to component device
>
> with a back link in the component device pointing to the enclosure
> component.
>
> The way components work, probably blowing away enclosure_component_class
> makes the most sense anyway.

OK, so this is the patch doing the above; is this what you had in mind?
We're now managing all the links.

James

---

diff --git a/drivers/misc/enclosure.c b/drivers/misc/enclosure.c
index fafb57f..0736cff 100644
--- a/drivers/misc/enclosure.c
+++ b/drivers/misc/enclosure.c
@@ -31,7 +31,6 @@
static LIST_HEAD(container_list);
static DEFINE_MUTEX(container_list_lock);
static struct class enclosure_class;
-static struct class enclosure_component_class;

/**
* enclosure_find - find an enclosure given a device
@@ -166,6 +165,40 @@ void enclosure_unregister(struct enclosure_device *edev)
}
EXPORT_SYMBOL_GPL(enclosure_unregister);

+#define ENCLOSURE_NAME_SIZE 64
+
+static void enclosure_link_name(struct enclosure_component *cdev, char *name)
+{
+ strcpy(name, "enclosure_device:");
+ strcat(name, cdev->cdev.bus_id);
+}
+
+static void enclosure_remove_links(struct enclosure_component *cdev)
+{
+ char name[ENCLOSURE_NAME_SIZE];
+
+ enclosure_link_name(cdev, name);
+ sysfs_remove_link(&cdev->dev->kobj, name);
+ sysfs_remove_link(&cdev->cdev.kobj, "device");
+}
+
+static int enclosure_add_links(struct enclosure_component *cdev)
+{
+ int error;
+ char name[ENCLOSURE_NAME_SIZE];
+
+ error = sysfs_create_link(&cdev->cdev.kobj, &cdev->dev->kobj, "device");
+ if (error)
+ return error;
+
+ enclosure_link_name(cdev, name);
+ error = sysfs_create_link(&cdev->dev->kobj, &cdev->cdev.kobj, name);
+ if (error)
+ sysfs_remove_link(&cdev->cdev.kobj, "device");
+
+ return error;
+}
+
static void enclosure_release(struct device *cdev)
{
struct enclosure_device *edev = to_enclosure_device(cdev);
@@ -178,10 +211,15 @@ static void enclosure_component_release(struct device *dev)
{
struct enclosure_component *cdev = to_enclosure_component(dev);

- put_device(cdev->dev);
+ if (cdev->dev) {
+ enclosure_remove_links(cdev);
+ put_device(cdev->dev);
+ }
put_device(dev->parent);
}

+static struct attribute_group *enclosure_groups[];
+
/**
* enclosure_component_register - add a particular component to an enclosure
* @edev: the enclosure to add the component
@@ -217,12 +255,14 @@ enclosure_component_register(struct enclosure_device *edev,
ecomp->number = number;
cdev = &ecomp->cdev;
cdev->parent = get_device(&edev->edev);
- cdev->class = &enclosure_component_class;
if (name)
snprintf(cdev->bus_id, BUS_ID_SIZE, "%s", name);
else
snprintf(cdev->bus_id, BUS_ID_SIZE, "%u", number);

+ cdev->release = enclosure_component_release;
+ cdev->groups = enclosure_groups;
+
err = device_register(cdev);
if (err)
ERR_PTR(err);
@@ -255,10 +295,12 @@ int enclosure_add_device(struct enclosure_device *edev, int component,

cdev = &edev->component[component];

- device_del(&cdev->cdev);
+ if (cdev->dev)
+ enclosure_remove_links(cdev);
+
put_device(cdev->dev);
cdev->dev = get_device(dev);
- return device_add(&cdev->cdev);
+ return enclosure_add_links(cdev);
}
EXPORT_SYMBOL_GPL(enclosure_add_device);

@@ -442,24 +484,32 @@ static ssize_t get_component_type(struct device *cdev,
}

-static struct device_attribute enclosure_component_attrs[] = {
- __ATTR(fault, S_IRUGO | S_IWUSR, get_component_fault,
- set_component_fault),
- __ATTR(status, S_IRUGO | S_IWUSR, get_component_status,
- set_component_status),
- __ATTR(active, S_IRUGO | S_IWUSR, get_component_active,
- set_component_active),
- __ATTR(locate, S_IRUGO | S_IWUSR, get_component_locate,
- set_component_locate),
- __ATTR(type, S_IRUGO, get_component_type, NULL),
- __ATTR_NULL
+static DEVICE_ATTR(fault, S_IRUGO | S_IWUSR, get_component_fault,
+ set_component_fault);
+static DEVICE_ATTR(status, S_IRUGO | S_IWUSR, get_component_status,
+ set_component_status);
+static DEVICE_ATTR(active, S_IRUGO | S_IWUSR, get_component_active,
+ set_component_active);
+static DEVICE_ATTR(locate, S_IRUGO | S_IWUSR, get_component_locate,
+ set_component_locate);
+static DEVICE_ATTR(type, S_IRUGO, get_component_type, NULL);
+
+static struct attribute *enclosure_component_attrs[] = {
+ &dev_attr_fault.attr,
+ &dev_attr_status.attr,
+ &dev_attr_active.attr,
+ &dev_attr_locate.attr,
+ &dev_attr_type.attr,
+ NULL
};

-static struct class enclosure_component_class = {
- .name = "enclosure_component",
- .owner = THIS_MODULE,
- .dev_attrs = enclosure_component_attrs,
- .dev_release = enclosure_component_release,
+static struct attribute_group enclosure_group = {
+ .attrs = enclosure_component_attrs,
+};
+
+static struct attribute_group *enclosure_groups[] = {
+ &enclosure_group,
+ NULL
};

static int __init enclosure_init(void)
@@ -469,20 +519,12 @@ static int __init enclosure_init(void)
err = class_register(&enclosure_class);
if (err)
return err;
- err = class_register(&enclosure_component_class);
- if (err)
- goto err_out;

return 0;
- err_out:
- class_unregister(&enclosure_class);
-
- return err;
}

static void __exit enclosure_exit(void)
{
- class_unregister(&enclosure_component_class);
class_unregister(&enclosure_class);
}