scsi: sg: Make sg_sysfs_class constant

Since commit 43a7206b0963 ("driver core: class: make class_register() take
a const *"), the driver core allows for struct class to be in read-only
memory, so move the sg_sysfs_class structure to be declared at build time
placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Link: https://lore.kernel.org/r/20240302-class_cleanup-scsi-v1-1-b9096b990e27@marliere.net
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 86210e4dd0d3530c65302723664b9ea5e9a6fc08..6ef6256246dfafb5a1084abaa5918cadffe069a7 100644 (file)
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1424,7 +1424,9 @@ static const struct file_operations sg_fops = {
        .llseek = no_llseek,
 };
 
-static struct class *sg_sysfs_class;
+static const struct class sg_sysfs_class = {
+       .name = "scsi_generic"
+};
 
 static int sg_sysfs_valid = 0;
 
@@ -1526,7 +1528,7 @@ sg_add_device(struct device *cl_dev)
        if (sg_sysfs_valid) {
                struct device *sg_class_member;
 
-               sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
+               sg_class_member = device_create(&sg_sysfs_class, cl_dev->parent,
                                                MKDEV(SCSI_GENERIC_MAJOR,
                                                      sdp->index),
                                                sdp, "%s", sdp->name);
@@ -1616,7 +1618,7 @@ sg_remove_device(struct device *cl_dev)
        read_unlock_irqrestore(&sdp->sfd_lock, iflags);
 
        sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
-       device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
+       device_destroy(&sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
        cdev_del(sdp->cdev);
        sdp->cdev = NULL;
 
@@ -1687,11 +1689,9 @@ init_sg(void)
                                    SG_MAX_DEVS, "sg");
        if (rc)
                return rc;
-        sg_sysfs_class = class_create("scsi_generic");
-        if ( IS_ERR(sg_sysfs_class) ) {
-               rc = PTR_ERR(sg_sysfs_class);
+       rc = class_register(&sg_sysfs_class);
+       if (rc)
                goto err_out;
-        }
        sg_sysfs_valid = 1;
        rc = scsi_register_interface(&sg_interface);
        if (0 == rc) {
@@ -1700,7 +1700,7 @@ init_sg(void)
 #endif                         /* CONFIG_SCSI_PROC_FS */
                return 0;
        }
-       class_destroy(sg_sysfs_class);
+       class_unregister(&sg_sysfs_class);
        register_sg_sysctls();
 err_out:
        unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
@@ -1715,7 +1715,7 @@ exit_sg(void)
        remove_proc_subtree("scsi/sg", NULL);
 #endif                         /* CONFIG_SCSI_PROC_FS */
        scsi_unregister_interface(&sg_interface);
-       class_destroy(sg_sysfs_class);
+       class_unregister(&sg_sysfs_class);
        sg_sysfs_valid = 0;
        unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
                                 SG_MAX_DEVS);