dca: make dca_class a static const structure

The driver core allows for struct class to be in read-only memory. Move
the dca_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>
Link: https://lore.kernel.org/r/20240412151726.189030-1-ivan.orlov0322@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/dca/dca-sysfs.c b/drivers/dca/dca-sysfs.c
index fcc83ede09093a8851eb4fad9c0b495b7ebe8ff7..b915c2b4601e60e905d5f8c56d0e2393d5d542e9 100644 (file)
--- a/drivers/dca/dca-sysfs.c
+++ b/drivers/dca/dca-sysfs.c
@@ -13,7 +13,9 @@
 #include <linux/gfp.h>
 #include <linux/export.h>
 
-static struct class *dca_class;
+static const struct class dca_class = {
+       .name = "dca",
+};
 static struct idr dca_idr;
 static spinlock_t dca_idr_lock;
 
@@ -22,14 +24,14 @@ int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
        struct device *cd;
        static int req_count;
 
-       cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
+       cd = device_create(&dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
                           "requester%d", req_count++);
        return PTR_ERR_OR_ZERO(cd);
 }
 
 void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
 {
-       device_destroy(dca_class, MKDEV(0, slot + 1));
+       device_destroy(&dca_class, MKDEV(0, slot + 1));
 }
 
 int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
@@ -49,7 +51,7 @@ int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
        if (ret < 0)
                return ret;
 
-       cd = device_create(dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
+       cd = device_create(&dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
        if (IS_ERR(cd)) {
                spin_lock(&dca_idr_lock);
                idr_remove(&dca_idr, dca->id);
@@ -71,20 +73,22 @@ void dca_sysfs_remove_provider(struct dca_provider *dca)
 
 int __init dca_sysfs_init(void)
 {
+       int err;
+
        idr_init(&dca_idr);
        spin_lock_init(&dca_idr_lock);
 
-       dca_class = class_create("dca");
-       if (IS_ERR(dca_class)) {
+       err = class_register(&dca_class);
+       if (err) {
                idr_destroy(&dca_idr);
-               return PTR_ERR(dca_class);
+               return err;
        }
        return 0;
 }
 
 void __exit dca_sysfs_exit(void)
 {
-       class_destroy(dca_class);
+       class_unregister(&dca_class);
        idr_destroy(&dca_idr);
 }