Re: [PATCH] mei: make mei_class a static const structure

[Ivan Orlov <ivan.orlov0322@gmail.com>]

On 8/11/23 23:40, Greg KH wrote:
> On Thu, Aug 10, 2023 at 11:46:52PM +0400, Ivan Orlov wrote:
>> Now that the driver core allows for struct class to be in read-only
>> memory, move the mei_class structure to be declared at build time
>> placing it into read-only memory, instead of having to be dynamically
>> allocated at boot time.
>>
>> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
>> ---
>>   drivers/misc/mei/main.c | 19 ++++++++++---------
>>   1 file changed, 10 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
>> index 51876da3fd65..902789d3106b 100644
>> --- a/drivers/misc/mei/main.c
>> +++ b/drivers/misc/mei/main.c
>> @@ -27,7 +27,9 @@
>>   #include "mei_dev.h"
>>   #include "client.h"
>>   
>> -static struct class *mei_class;
>> +static const struct class mei_class = {
>> +	.name = "mei",
>> +};
>>   static dev_t mei_devt;
> 
> Extra line after the new structure?
> 
>>   #define MEI_MAX_DEVS  MINORMASK
>>   static DEFINE_MUTEX(mei_minor_lock);
>> @@ -1115,7 +1117,7 @@ void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state)
>>   
>>   	dev->dev_state = state;
>>   
>> -	clsdev = class_find_device_by_devt(mei_class, dev->cdev.dev);
>> +	clsdev = class_find_device_by_devt(&mei_class, dev->cdev.dev);
>>   	if (clsdev) {
>>   		sysfs_notify(&clsdev->kobj, NULL, "dev_state");
>>   		put_device(clsdev);
>> @@ -1232,7 +1234,7 @@ int mei_register(struct mei_device *dev, struct device *parent)
>>   		goto err_dev_add;
>>   	}
>>   
>> -	clsdev = device_create_with_groups(mei_class, parent, devno,
>> +	clsdev = device_create_with_groups(&mei_class, parent, devno,
>>   					   dev, mei_groups,
>>   					   "mei%d", dev->minor);
>>   
>> @@ -1264,7 +1266,7 @@ void mei_deregister(struct mei_device *dev)
>>   
>>   	mei_dbgfs_deregister(dev);
>>   
>> -	device_destroy(mei_class, devno);
>> +	device_destroy(&mei_class, devno);
>>   
>>   	mei_minor_free(dev);
>>   }
>> @@ -1274,10 +1276,9 @@ static int __init mei_init(void)
>>   {
>>   	int ret;
>>   
>> -	mei_class = class_create("mei");
>> -	if (IS_ERR(mei_class)) {
>> +	ret = class_register(&mei_class);
>> +	if (ret) {
>>   		pr_err("couldn't create class\n");
> 
> This message doesn't make sense anymore.  No need for it either, just
> remove it and do a simple:
> 		return err;
> here instead.
> 
> thanks,
> 
> greg k-h


Hi Greg,

Thank you for the review, I'll make the suggested changes and send you 
the V2.

--
Kind regards,
Ivan Orlov