Añadidos pidevice y hang

1 files changed, 104 insertions, 0 deletions

diff --git a/pidevice/pidevice.c b/pidevice/pidevice.c
new file mode 100644
index 0000000..3c5d3b4
--- /dev/null
+++ b/pidevice/pidevice.c
@@ -0,0 +1,104 @@
+#include <asm/uaccess.h>
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/kdev_t.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+
+static char devname[] = "pidevice";
+static char modname[] = "pidevice.ko";
+static dev_t mydev = 0;
+static struct cdev cdev;
+static struct task_struct *mytask;
+static struct task_struct *parent;
+
+static int count = 1;
+
+int pidev_open(struct inode *i, struct file *filp)
+{
+	count = 1;
+	printk(KERN_ALERT "Device (%d-%d) opened\n",
+			imajor(i), iminor(i));
+	printk(KERN_ALERT "Mode: %c%c\n", filp->f_mode & FMODE_READ ? 'R' : '-',
+			filp->f_mode & FMODE_WRITE ? 'W' : '-');
+	return 0;
+}
+
+ssize_t pidev_read(struct file *filp, char __user *buf,
+		size_t len, loff_t *off)
+{
+	if (count--) {
+		copy_to_user(buf, modname, 12);
+		return 12;
+	} else {
+		return 0;
+	}
+}
+
+ssize_t pidev_write(struct file *filp, const char __user *buf,
+		size_t len, loff_t *off)
+{
+	char localbuf[40];
+	copy_from_user(localbuf, buf, 40);
+	localbuf[len] = '\0';
+
+	printk(KERN_ALERT "Recibido: %s", localbuf);
+	return -EPERM;
+}
+
+struct file_operations fops = {
+	.owner = THIS_MODULE,
+	.open = pidev_open,
+	.read = pidev_read,
+	.write = pidev_write,
+};
+
+static void show_processes(void)
+{
+	mytask = current;
+	parent = mytask->parent;
+
+	while (mytask->pid != parent->pid) {
+		printk(KERN_ALERT "current: %s (%d) - parent: %s (%d)\n",
+				mytask->comm, mytask->pid, parent->comm, parent->pid);
+		mytask = mytask->parent;
+		parent = mytask->parent;
+	}
+}
+
+static int __init init(void)
+{
+	int err;
+
+	printk(KERN_ALERT "%s loaded by %s (%d)\n",
+			modname, current->comm, current->pid);
+
+	if ((err = alloc_chrdev_region(&mydev, 0, 1, devname)))
+		printk(KERN_ALERT "ERROR in alloc_chrdev_region: %d\n", err);
+	else
+		printk(KERN_ALERT "%s successfully registered with %d %d numbers\n",
+				devname, MAJOR(mydev), MINOR(mydev));
+
+	cdev_init(&cdev, &fops);
+	cdev.owner = THIS_MODULE;
+	if ((err = cdev_add(&cdev, mydev, 1)))
+		printk(KERN_ALERT "ERROR in cdev_add: %d\n", err);
+
+	return 0;
+}
+
+static void __exit exit(void)
+{
+	unregister_chrdev_region(mydev, 1);
+	cdev_del(&cdev);
+	printk(KERN_ALERT "%s unloaded\n", modname);
+}
+
+module_init(init);
+module_exit(exit);
+
+MODULE_LICENSE("GPL");