[PATCH 4/5] scsi: ch: make ch_sysfs_class constant

From: Ricardo B. Marliere
Date: Sat Mar 02 2024 - 11:49:00 EST


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 ch_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@xxxxxxxxxxxxxxxxxxx>
Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ricardo B. Marliere <ricardo@xxxxxxxxxxxx>
---
drivers/scsi/ch.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index 1befcd5b2a0f..fa07a6f54003 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -102,7 +102,9 @@ do { \

#define MAX_RETRIES 1

-static struct class * ch_sysfs_class;
+static const struct class ch_sysfs_class = {
+ .name = "scsi_changer",
+};

typedef struct {
struct kref ref;
@@ -930,7 +932,7 @@ static int ch_probe(struct device *dev)
mutex_init(&ch->lock);
kref_init(&ch->ref);
ch->device = sd;
- class_dev = device_create(ch_sysfs_class, dev,
+ class_dev = device_create(&ch_sysfs_class, dev,
MKDEV(SCSI_CHANGER_MAJOR, ch->minor), ch,
"s%s", ch->name);
if (IS_ERR(class_dev)) {
@@ -955,7 +957,7 @@ static int ch_probe(struct device *dev)

return 0;
destroy_dev:
- device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR, ch->minor));
+ device_destroy(&ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR, ch->minor));
put_device:
scsi_device_put(sd);
remove_idr:
@@ -974,7 +976,7 @@ static int ch_remove(struct device *dev)
dev_set_drvdata(dev, NULL);
spin_unlock(&ch_index_lock);

- device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR,ch->minor));
+ device_destroy(&ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR, ch->minor));
scsi_device_put(ch->device);
kref_put(&ch->ref, ch_destroy);
return 0;
@@ -1003,11 +1005,9 @@ static int __init init_ch_module(void)
int rc;

printk(KERN_INFO "SCSI Media Changer driver v" VERSION " \n");
- ch_sysfs_class = class_create("scsi_changer");
- if (IS_ERR(ch_sysfs_class)) {
- rc = PTR_ERR(ch_sysfs_class);
+ rc = class_register(&ch_sysfs_class);
+ if (rc)
return rc;
- }
rc = register_chrdev(SCSI_CHANGER_MAJOR,"ch",&changer_fops);
if (rc < 0) {
printk("Unable to get major %d for SCSI-Changer\n",
@@ -1022,7 +1022,7 @@ static int __init init_ch_module(void)
fail2:
unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
fail1:
- class_destroy(ch_sysfs_class);
+ class_unregister(&ch_sysfs_class);
return rc;
}

@@ -1030,7 +1030,7 @@ static void __exit exit_ch_module(void)
{
scsi_unregister_driver(&ch_template.gendrv);
unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
- class_destroy(ch_sysfs_class);
+ class_unregister(&ch_sysfs_class);
idr_destroy(&ch_index_idr);
}


--
2.43.0