Merge pull request #328 from esa-tu-darmstadt/feature/fix-multidevice-access-mode

Add list of acquired devices to miscdev

runtime/kernel/tlkm/tlkm.c

@@ -65,32 +65,39 @@ void tlkm_exit(void)
 
 static int tlkm_miscdev_open(struct inode *inode, struct file *filp)
 {
-	tlkm_ioctl_data *tmp = NULL;
+	struct tlkm_ioctl_dev_list_head *tmp = NULL;
 	atomic_inc(&opened_counter);
 	LOG(TLKM_LF_MODULE, "Device is now opened %d times.",
 	    atomic_read(&opened_counter));
 	filp->private_data =
-		(tlkm_ioctl_data *)kmalloc(sizeof(tlkm_ioctl_data), GFP_KERNEL);
+		kmalloc(sizeof(struct tlkm_ioctl_dev_list_head), GFP_KERNEL);
 	if (!filp->private_data)
 		return -ENODEV;
-	tmp = (tlkm_ioctl_data *)filp->private_data;
-	tmp->pdev = NULL;
+	tmp = filp->private_data;
+	INIT_LIST_HEAD(&tmp->head);
 	return 0;
 }
 
 static int tlkm_miscdev_release(struct inode *inode, struct file *filp)
 {
-	tlkm_ioctl_data *tmp = NULL;
+	struct tlkm_ioctl_dev_list_head *dev_list;
+	struct tlkm_ioctl_dev_list_entry *entry, *tmp;
+
 	atomic_dec(&opened_counter);
 	LOG(TLKM_LF_MODULE, "Device is still opened %d times.",
 	    atomic_read(&opened_counter));
-	if (filp->private_data != NULL) {
-		tmp = (tlkm_ioctl_data *)filp->private_data;
-		if (tmp->pdev) {
-			tlkm_device_release(tmp->pdev, tmp->access);
-		}
-		kfree(filp->private_data);
-		filp->private_data = NULL;
+
+	dev_list = filp->private_data;
+	if (!dev_list) {
+		ERR("device list not initialized");
+		return -ENODEV;
+	}
+	list_for_each_entry_safe(entry, tmp, &dev_list->head, list) {
+		tlkm_device_release(entry->pdev, entry->access);
+		list_del(&entry->list);
+		kfree(entry);
 	}
+	kfree(filp->private_data);
+	filp->private_data = NULL;
 	return 0;
 }

runtime/kernel/tlkm/tlkm_ioctl.c

@@ -76,32 +76,62 @@ tlkm_ioctl_enum_devices(struct file *fp, unsigned int ioctl,
 static long tlkm_ioctl_create_device(struct file *fp, unsigned int ioctl,
 				     struct tlkm_ioctl_device_cmd __user *cmd)
 {
-	tlkm_ioctl_data *tmp = NULL;
+	int ret = 0;
+	struct tlkm_ioctl_dev_list_head *dev_list = NULL;
+	struct tlkm_ioctl_dev_list_entry *new;
 	struct tlkm_ioctl_device_cmd kc;
 	if (copy_from_user(&kc, (void __user *)cmd, sizeof(kc))) {
 		ERR("could not copy create device command from user space");
 		return -EACCES;
 	}
 	LOG(TLKM_LF_IOCTL, "create device #%02u command received", kc.dev_id);
-	tmp = (tlkm_ioctl_data *)fp->private_data;
-	tmp->pdev = tlkm_bus_get_device(kc.dev_id);
-	tmp->access = kc.access;
-	return tlkm_device_acquire(tlkm_bus_get_device(kc.dev_id), kc.access);
+
+	dev_list = fp->private_data;
+	new = kmalloc(sizeof(*new), GFP_KERNEL);
+	if (!new) {
+		ERR("could not allocate memory for list entry");
+		return -ENOMEM;
+	}
+	new->pdev = tlkm_bus_get_device(kc.dev_id);
+	new->access = kc.access;
+	ret = tlkm_device_acquire(tlkm_bus_get_device(kc.dev_id), kc.access);
+	if (ret)
+		kfree(new);
+	else
+		list_add(&new->list, &dev_list->head);
+
+	return ret;
 }
 
 static long tlkm_ioctl_destroy_device(struct file *fp, unsigned int ioctl,
 				      struct tlkm_ioctl_device_cmd __user *cmd)
 {
-	tlkm_ioctl_data *tmp = NULL;
+	struct tlkm_device *dev;
+	struct tlkm_ioctl_dev_list_head *dev_list;
+	struct tlkm_ioctl_dev_list_entry *entry = NULL, *iter;
 	struct tlkm_ioctl_device_cmd kc;
 	if (copy_from_user(&kc, (void __user *)cmd, sizeof(kc))) {
 		ERR("could not copy destroy device command from user space");
 		return -EACCES;
 	}
 	LOG(TLKM_LF_IOCTL, "destroy device #%02u command received", kc.dev_id);
-	tlkm_device_release(tlkm_bus_get_device(kc.dev_id), kc.access);
-	tmp = (tlkm_ioctl_data *)fp->private_data;
-	tmp->pdev = NULL;
+
+	dev = tlkm_bus_get_device(kc.dev_id);
+	dev_list = fp->private_data;
+	list_for_each_entry(iter, &dev_list->head, list) {
+		if (iter->pdev == dev && iter->access == kc.access) {
+			entry = iter;
+			break;
+		}
+	}
+	if (!entry) {
+		ERR("No matching device acquired");
+		return -ENODEV;
+	}
+
+	tlkm_device_release(dev, kc.access);
+	list_del(&entry->list);
+	kfree(entry);
 	return 0;
 }
 

runtime/kernel/tlkm/tlkm_ioctl.h

@@ -22,10 +22,15 @@
 
 #include <linux/fs.h>
 
-typedef struct {
+struct tlkm_ioctl_dev_list_head {
+	struct list_head head;
+};
+
+struct tlkm_ioctl_dev_list_entry {
+	struct list_head list;
 	struct tlkm_device *pdev;
 	tlkm_access_t access;
-} tlkm_ioctl_data;
+};
 
 long tlkm_ioctl_ioctl(struct file *fp, unsigned int ioctl, unsigned long data);