Simple hello world module.

diff --git a/Makefile b/Makefile
new file mode 100644 (file)
index 0000000..d4757ee
--- /dev/null
+++ b/Makefile
@@ -0,0 +1 @@
+obj-m := hello.o

diff --git a/hello.c b/hello.c
new file mode 100644 (file)
index 0000000..8a5a20b
--- /dev/null
+++ b/hello.c
@@ -0,0 +1,61 @@
+/*
+ *  Copyright (C) 2010  Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>");
+MODULE_DESCRIPTION("Hello, world");
+
+static int size = 1;
+module_param_named(size, size, int, S_IRUGO | S_IWUSR);
+
+struct hello {
+       int times;
+       char greeting[0];
+};
+
+static struct hello *hello;
+
+static char default_greeting[] = "Hello, world!\n";
+
+static int hello_init(void)
+{
+       hello = kmalloc(sizeof(*hello) + sizeof(default_greeting), GFP_KERNEL);
+       if (!hello)
+               return -ENOMEM;
+       memcpy(hello->greeting, default_greeting, sizeof(default_greeting));
+       printk("%s\n", hello->greeting);
+       printk("%p %p %p\n", hello, hello->greeting,
+               container_of(&hello->greeting, struct hello, greeting));
+       printk("size %d\n", ARRAY_SIZE(default_greeting));
+       return 0;
+}
+
+static __exit void hello_exit(void)
+{
+       kfree(hello);
+}
+
+module_init(hello_init);
+module_exit(hello_exit);