RDMA: Make all 'class' structures const

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

Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Cc: "Md. Haris Iqbal" <haris.iqbal@ionos.com>
Cc: Jack Wang <jinpu.wang@ionos.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Yishai Hadas <yishaih@nvidia.com>
Cc: Ivan Orlov <ivan.orlov0322@gmail.com>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/2023080427-commuting-crewless-cbee@gregkh
Signed-off-by: Leon Romanovsky <leon@kernel.org>

2 files changed, 40 insertions, 49 deletions

diff --git a/drivers/infiniband/hw/hfi1/device.c b/drivers/infiniband/hw/hfi1/device.c
index 05be0d119f79..b0a00b7aaec5 100644
--- a/drivers/infiniband/hw/hfi1/device.c
+++ b/drivers/infiniband/hw/hfi1/device.c
@@ -10,8 +10,29 @@
 #include "hfi.h"
 #include "device.h"
 
-static struct class *class;
-static struct class *user_class;
+static char *hfi1_devnode(const struct device *dev, umode_t *mode)
+{
+	if (mode)
+		*mode = 0600;
+	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
+}
+
+static const struct class class = {
+	.name = "hfi1",
+	.devnode = hfi1_devnode,
+};
+
+static char *hfi1_user_devnode(const struct device *dev, umode_t *mode)
+{
+	if (mode)
+		*mode = 0666;
+	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
+}
+
+static const struct class user_class = {
+	.name = "hfi1_user",
+	.devnode = hfi1_user_devnode,
+};
 static dev_t hfi1_dev;
 
 int hfi1_cdev_init(int minor, const char *name,
@@ -37,9 +58,9 @@ int hfi1_cdev_init(int minor, const char *name,
 	}
 
 	if (user_accessible)
-		device = device_create(user_class, NULL, dev, NULL, "%s", name);
+		device = device_create(&user_class, NULL, dev, NULL, "%s", name);
 	else
-		device = device_create(class, NULL, dev, NULL, "%s", name);
+		device = device_create(&class, NULL, dev, NULL, "%s", name);
 
 	if (IS_ERR(device)) {
 		ret = PTR_ERR(device);
@@ -72,26 +93,6 @@ const char *class_name(void)
 	return hfi1_class_name;
 }
 
-static char *hfi1_devnode(const struct device *dev, umode_t *mode)
-{
-	if (mode)
-		*mode = 0600;
-	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
-}
-
-static const char *hfi1_class_name_user = "hfi1_user";
-static const char *class_name_user(void)
-{
-	return hfi1_class_name_user;
-}
-
-static char *hfi1_user_devnode(const struct device *dev, umode_t *mode)
-{
-	if (mode)
-		*mode = 0666;
-	return kasprintf(GFP_KERNEL, "%s", dev_name(dev));
-}
-
 int __init dev_init(void)
 {
 	int ret;
@@ -102,27 +103,21 @@ int __init dev_init(void)
 		goto done;
 	}
 
-	class = class_create(class_name());
-	if (IS_ERR(class)) {
-		ret = PTR_ERR(class);
+	ret = class_register(&class);
+	if (ret) {
 		pr_err("Could not create device class (err %d)\n", -ret);
 		unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
 		goto done;
 	}
-	class->devnode = hfi1_devnode;
 
-	user_class = class_create(class_name_user());
-	if (IS_ERR(user_class)) {
-		ret = PTR_ERR(user_class);
+	ret = class_register(&user_class);
+	if (ret) {
 		pr_err("Could not create device class for user accessible files (err %d)\n",
 		       -ret);
-		class_destroy(class);
-		class = NULL;
-		user_class = NULL;
+		class_unregister(&class);
 		unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
 		goto done;
 	}
-	user_class->devnode = hfi1_user_devnode;
 
 done:
 	return ret;
@@ -130,11 +125,8 @@ done:
 
 void dev_cleanup(void)
 {
-	class_destroy(class);
-	class = NULL;
-
-	class_destroy(user_class);
-	user_class = NULL;
+	class_unregister(&class);
+	class_unregister(&user_class);
 
 	unregister_chrdev_region(hfi1_dev, HFI1_NMINORS);
 }
diff --git a/drivers/infiniband/hw/qib/qib_file_ops.c b/drivers/infiniband/hw/qib/qib_file_ops.c
index ef85bc8d9384..152952127f13 100644
--- a/drivers/infiniband/hw/qib/qib_file_ops.c
+++ b/drivers/infiniband/hw/qib/qib_file_ops.c
@@ -2250,7 +2250,9 @@ static ssize_t qib_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	return qib_user_sdma_writev(rcd, pq, iter_iov(from), from->nr_segs);
 }
 
-static struct class *qib_class;
+static const struct class qib_class = {
+	.name = "ipath",
+};
 static dev_t qib_dev;
 
 int qib_cdev_init(int minor, const char *name,
@@ -2281,7 +2283,7 @@ int qib_cdev_init(int minor, const char *name,
 		goto err_cdev;
 	}
 
-	device = device_create(qib_class, NULL, dev, NULL, "%s", name);
+	device = device_create(&qib_class, NULL, dev, NULL, "%s", name);
 	if (!IS_ERR(device))
 		goto done;
 	ret = PTR_ERR(device);
@@ -2325,9 +2327,8 @@ int __init qib_dev_init(void)
 		goto done;
 	}
 
-	qib_class = class_create("ipath");
-	if (IS_ERR(qib_class)) {
-		ret = PTR_ERR(qib_class);
+	ret = class_register(&qib_class);
+	if (ret) {
 		pr_err("Could not create device class (err %d)\n", -ret);
 		unregister_chrdev_region(qib_dev, QIB_NMINORS);
 	}
@@ -2338,10 +2339,8 @@ done:
 
 void qib_dev_cleanup(void)
 {
-	if (qib_class) {
-		class_destroy(qib_class);
-		qib_class = NULL;
-	}
+	if (class_is_registered(&qib_class))
+		class_unregister(&qib_class);
 
 	unregister_chrdev_region(qib_dev, QIB_NMINORS);
 }