[PATCH 1/6] s390: zcrypt: make zcrypt_class constant

From: Ricardo B. Marliere
Date: Tue Mar 05 2024 - 06:28:24 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 zcrypt_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/s390/crypto/zcrypt_api.c | 33 +++++++++++++++++----------------
1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c
index e8742757085b..d0358bb6ccf2 100644
--- a/drivers/s390/crypto/zcrypt_api.c
+++ b/drivers/s390/crypto/zcrypt_api.c
@@ -116,7 +116,11 @@ EXPORT_SYMBOL(zcrypt_msgtype);

struct zcdn_device;

-static struct class *zcrypt_class;
+static void zcdn_device_release(struct device *dev);
+static const struct class zcrypt_class = {
+ .name = ZCRYPT_NAME,
+ .dev_release = zcdn_device_release,
+};
static dev_t zcrypt_devt;
static struct cdev zcrypt_cdev;

@@ -139,7 +143,7 @@ static int zcdn_destroy(const char *name);
*/
static inline struct zcdn_device *find_zcdndev_by_name(const char *name)
{
- struct device *dev = class_find_device_by_name(zcrypt_class, name);
+ struct device *dev = class_find_device_by_name(&zcrypt_class, name);

return dev ? to_zcdn_dev(dev) : NULL;
}
@@ -151,7 +155,7 @@ static inline struct zcdn_device *find_zcdndev_by_name(const char *name)
*/
static inline struct zcdn_device *find_zcdndev_by_devt(dev_t devt)
{
- struct device *dev = class_find_device_by_devt(zcrypt_class, devt);
+ struct device *dev = class_find_device_by_devt(&zcrypt_class, devt);

return dev ? to_zcdn_dev(dev) : NULL;
}
@@ -405,7 +409,7 @@ static int zcdn_create(const char *name)
goto unlockout;
}
zcdndev->device.release = zcdn_device_release;
- zcdndev->device.class = zcrypt_class;
+ zcdndev->device.class = &zcrypt_class;
zcdndev->device.devt = devt;
zcdndev->device.groups = zcdn_dev_attr_groups;
if (name[0])
@@ -2067,12 +2071,9 @@ static int __init zcdn_init(void)
int rc;

/* create a new class 'zcrypt' */
- zcrypt_class = class_create(ZCRYPT_NAME);
- if (IS_ERR(zcrypt_class)) {
- rc = PTR_ERR(zcrypt_class);
+ rc = class_register(&zcrypt_class);
+ if (rc)
goto out_class_create_failed;
- }
- zcrypt_class->dev_release = zcdn_device_release;

/* alloc device minor range */
rc = alloc_chrdev_region(&zcrypt_devt,
@@ -2088,35 +2089,35 @@ static int __init zcdn_init(void)
goto out_cdev_add_failed;

/* need some class specific sysfs attributes */
- rc = class_create_file(zcrypt_class, &class_attr_zcdn_create);
+ rc = class_create_file(&zcrypt_class, &class_attr_zcdn_create);
if (rc)
goto out_class_create_file_1_failed;
- rc = class_create_file(zcrypt_class, &class_attr_zcdn_destroy);
+ rc = class_create_file(&zcrypt_class, &class_attr_zcdn_destroy);
if (rc)
goto out_class_create_file_2_failed;

return 0;

out_class_create_file_2_failed:
- class_remove_file(zcrypt_class, &class_attr_zcdn_create);
+ class_remove_file(&zcrypt_class, &class_attr_zcdn_create);
out_class_create_file_1_failed:
cdev_del(&zcrypt_cdev);
out_cdev_add_failed:
unregister_chrdev_region(zcrypt_devt, ZCRYPT_MAX_MINOR_NODES);
out_alloc_chrdev_failed:
- class_destroy(zcrypt_class);
+ class_unregister(&zcrypt_class);
out_class_create_failed:
return rc;
}

static void zcdn_exit(void)
{
- class_remove_file(zcrypt_class, &class_attr_zcdn_create);
- class_remove_file(zcrypt_class, &class_attr_zcdn_destroy);
+ class_remove_file(&zcrypt_class, &class_attr_zcdn_create);
+ class_remove_file(&zcrypt_class, &class_attr_zcdn_destroy);
zcdn_destroy_all();
cdev_del(&zcrypt_cdev);
unregister_chrdev_region(zcrypt_devt, ZCRYPT_MAX_MINOR_NODES);
- class_destroy(zcrypt_class);
+ class_unregister(&zcrypt_class);
}

/*

--
2.43.0