format files to comply with kernel coding standards, rename .config to config

01/main.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/printk.h>

04/hello-world.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/printk.h>

05/main.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs.h>

05/rw.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs.h>
@@ -9,15 +10,18 @@
 ssize_t dev_read(struct file *f, char __user *buf, size_t len, loff_t *off);
 ssize_t dev_write(struct file *f, const char __user *buf, size_t len, loff_t *off);
 
-ssize_t dev_read(struct file *f, char __user *buf, size_t len, loff_t *off) {
+ssize_t dev_read(struct file *f, char __user *buf, size_t len, loff_t *off)
+{
 	char msg[] = VALUE;
+
 	pr_info("someone read from the file\n");
 	return simple_read_from_buffer(buf, len, off, msg, sizeof(msg) - 1);
 }
 
-
+ssize_t dev_write(struct file *f, const char __user *buf, size_t len, loff_t *off)
-ssize_t dev_write(struct file *f, const char __user *buf, size_t len, loff_t *off) {
+{
 	char kbuf[64];
+
 	if (len > sizeof(kbuf) - 1)
 		return -EINVAL;
 	if (copy_from_user(kbuf, buf, len))
@@ -25,8 +29,7 @@ ssize_t dev_write(struct file *f, const char __user *buf, size_t len, loff_t *of
 
 	kbuf[len] = '\0';
 
-    if (strcmp(kbuf, VALUE) == 0)
+	if (strcmp(kbuf, VALUE) == 0) {
-	{
 		pr_info("someone wrote the right string\n");
 		return len;
 	}

07/foo.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs.h>
@@ -13,7 +14,7 @@ ssize_t foo_write(struct file *f, const char __user *buf, size_t len, loff_t *of
 int init_foo(void);
 
 char buffer[PAGE_SIZE];
-size_t buffer_len = 0;
+size_t buffer_len;
 DEFINE_MUTEX(rw_lock);
 
 static const struct file_operations fops = {
@@ -39,8 +40,7 @@ ssize_t foo_write(struct file *f, const char __user *buf, size_t len, loff_t *of
 	if (len > sizeof(buffer))
 		return -EINVAL;
 	mutex_lock(&rw_lock);
-	if (copy_from_user(buffer, buf, len))
+	if (copy_from_user(buffer, buf, len)) {
-	{
 		mutex_unlock(&rw_lock);
 		return -EINVAL;
 	}
@@ -55,6 +55,7 @@ int init_foo(void)
 
 	mutex_init(&rw_lock);
 	ret = debugfs_create_file("foo", 0644, module_dir, NULL, &fops);
-	if (IS_ERR(ret)) return PTR_ERR(ret);
+	if (IS_ERR(ret))
+		return PTR_ERR(ret);
 	return 0;
 }

07/id.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs.h>
@@ -21,6 +22,7 @@ static const struct file_operations fops = {
 ssize_t id_read(struct file *f, char __user *buf, size_t len, loff_t *off)
 {
 	char msg[] = VALUE;
+
 	pr_info("someone read from the file\n");
 	return simple_read_from_buffer(buf, len, off, msg, sizeof(msg) - 1);
 }
@@ -29,6 +31,7 @@ ssize_t id_read(struct file *f, char __user *buf, size_t len, loff_t *off)
 ssize_t id_write(struct file *f, const char __user *buf, size_t len, loff_t *off)
 {
 	char kbuf[64];
+
 	if (len > sizeof(kbuf) - 1)
 		return -EINVAL;
 	if (copy_from_user(kbuf, buf, len))
@@ -47,6 +50,7 @@ ssize_t id_write(struct file *f, const char __user *buf, size_t len, loff_t *off
 int init_id(void)
 {
 	struct dentry *ret;
+
 	ret = debugfs_create_file("id", 0666, module_dir, NULL, &fops);
 	if (IS_ERR(ret))
 		return PTR_ERR(ret);

07/main.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/fs.h>
@@ -27,9 +28,11 @@ static int __init fortytwo_debug_init(void)
 	debugfs_create_u64("jiffies", 0444, module_dir, (uint64_t *)(&jiffies));
 
 	err = init_id();
-	if (err) return err;
+	if (err)
+		return err;
 	err = init_foo();
-	if(err) return err;
+	if (err)
+		return err;
 	return 0;
 }
 
@@ -41,4 +44,3 @@ static void __exit fortytwo_debug_exit(void)
 
 module_init(fortytwo_debug_init);
 module_exit(fortytwo_debug_exit);
-

09/main.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/module.h>
@@ -30,7 +31,8 @@ static const struct proc_ops proc_fops = {
 static int __init mounts_init(void)
 {
 	proc_file = proc_create("mymounts", 0444, 0, &proc_fops);
-	if(IS_ERR(proc_file)) return PTR_ERR(proc_file);
+	if (IS_ERR(proc_file))
+		return PTR_ERR(proc_file);
 	return 0;
 }
 
@@ -41,4 +43,3 @@ static void __exit mounts_exit(void)
 
 module_init(mounts_init);
 module_exit(mounts_exit);
-

09/rw.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/module.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
@@ -21,8 +22,7 @@ int list_mounts(struct seq_file *m, void *v)
 	cur = current->nsproxy->mnt_ns->mnt_first_node;
 
 	buf = kmalloc(sizeof(char) * PATH_MAX, GFP_KERNEL);
-	while(cur)
+	while (cur) {
-	{
 		mnt = rb_entry(cur, struct mount, mnt_node);
 
 		struct path p = {