uacce: make uacce_class constant

Now that the driver core allows for struct class to be in read-only
memory, we should make all 'class' structures declared at build time
placing them into read-only memory, instead of having to be dynamically
allocated at runtime.

Cc: Zhou Wang <wangzhou1@hisilicon.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-accelerators@lists.ozlabs.org
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Link: https://lore.kernel.org/r/2023102458-designate-vicinity-4c86@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
index 930c252..bdc2e6f 100644 (file)
--- a/drivers/misc/uacce/uacce.c
+++ b/drivers/misc/uacce/uacce.c
@@ -7,10 +7,13 @@
 #include <linux/slab.h>
 #include <linux/uacce.h>
 
-static struct class *uacce_class;
 static dev_t uacce_devt;
 static DEFINE_XARRAY_ALLOC(uacce_xa);
 
+static const struct class uacce_class = {
+       .name = UACCE_NAME,
+};
+
 /*
  * If the parent driver or the device disappears, the queue state is invalid and
  * ops are not usable anymore.
@@ -530,7 +533,7 @@ struct uacce_device *uacce_alloc(struct device *parent,
        mutex_init(&uacce->mutex);
        device_initialize(&uacce->dev);
        uacce->dev.devt = MKDEV(MAJOR(uacce_devt), uacce->dev_id);
-       uacce->dev.class = uacce_class;
+       uacce->dev.class = &uacce_class;
        uacce->dev.groups = uacce_dev_groups;
        uacce->dev.parent = uacce->parent;
        uacce->dev.release = uacce_release;
@@ -623,13 +626,13 @@ static int __init uacce_init(void)
 {
        int ret;
 
-       uacce_class = class_create(UACCE_NAME);
-       if (IS_ERR(uacce_class))
-               return PTR_ERR(uacce_class);
+       ret = class_register(&uacce_class);
+       if (ret)
+               return ret;
 
        ret = alloc_chrdev_region(&uacce_devt, 0, MINORMASK, UACCE_NAME);
        if (ret)
-               class_destroy(uacce_class);
+               class_unregister(&uacce_class);
 
        return ret;
 }
@@ -637,7 +640,7 @@ static int __init uacce_init(void)
 static __exit void uacce_exit(void)
 {
        unregister_chrdev_region(uacce_devt, MINORMASK);
-       class_destroy(uacce_class);
+       class_unregister(&uacce_class);
 }
 
 subsys_initcall(uacce_init);