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

[Ivan Orlov]

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@xxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
> > ---
> >   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