add assignement 00 to 08

05/Makefile

@@ -0,0 +1,9 @@
+obj-m += fortytwo.o 
+fortytwo-y = main.o rw.o
+PWD := $(CURDIR) 
+
+all: 
+	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules 
+
+clean: 
+	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean

05/boot.log

@@ -0,0 +1,6 @@
+[10006.564959] creating fortytwo misc device
+[10011.739012] someone read from the file
+[10011.740989] someone read from the file
+[10026.526506] someone wrote the wrong string
+[10031.246367] someone wrote the right string
+[10068.207415] removing forytwo misc device

05/main.c

@@ -0,0 +1,42 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/uaccess.h>
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("hello world module");
+
+#define FILENAME "fortytwo"
+
+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);
+
+static const struct file_operations fops = {
+    .owner = THIS_MODULE,
+    .read = dev_read,
+    .write = dev_write,
+};
+
+static struct miscdevice dev = {
+    .minor = MISC_DYNAMIC_MINOR,
+    .name = FILENAME,
+    .fops = &fops,
+    .mode = 0666,
+};
+
+static int __init fortytwo_init(void) 
+{ 
+	pr_info("creating fortytwo misc device\n");
+	return misc_register(&dev);
+} 
+
+static void __exit fortytwo_exit(void) 
+{ 
+	pr_info("removing forytwo misc device\n"); 
+	misc_deregister(&dev);
+} 
+
+module_init(fortytwo_init); 
+module_exit(fortytwo_exit);
+

05/rw.c

@@ -0,0 +1,35 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/uaccess.h>
+
+#define VALUE "tomoron"
+
+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) {
+    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) {
+    char kbuf[64];
+    if (len > sizeof(kbuf) - 1)
+        return -EINVAL;
+    if (copy_from_user(kbuf, buf, len))
+        return -EINVAL;
+
+    kbuf[len] = '\0';
+
+    if (strcmp(kbuf, VALUE) == 0)
+	{
+		pr_info("someone wrote the right string\n");
+        return len;
+	}
+	pr_info("someone wrote the wrong string\n");
+    return -EINVAL;
+}