[ALSA] return ENODEV for disconnected devices
Modules: ALSA Core
Add dummy functions that return -ENODEV for the struct file_operations
of a disconnected device. Without such functions, userspace would get
ENOTTY.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
diff --git a/sound/core/init.c b/sound/core/init.c
index 17fbd6c..ad68761 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -169,11 +169,44 @@
return NULL;
}
+static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig)
+{
+ return -ENODEV;
+}
+
+static ssize_t snd_disconnect_read(struct file *file, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return -ENODEV;
+}
+
+static ssize_t snd_disconnect_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *offset)
+{
+ return -ENODEV;
+}
+
static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
{
return POLLERR | POLLNVAL;
}
+static long snd_disconnect_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ return -ENODEV;
+}
+
+static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ return -ENODEV;
+}
+
+static int snd_disconnect_fasync(int fd, struct file *file, int on)
+{
+ return -ENODEV;
+}
+
/**
* snd_card_disconnect - disconnect all APIs from the file-operations (user space)
* @card: soundcard structure
@@ -224,7 +257,16 @@
memset(f_ops, 0, sizeof(*f_ops));
f_ops->owner = file->f_op->owner;
f_ops->release = file->f_op->release;
+ f_ops->llseek = snd_disconnect_llseek;
+ f_ops->read = snd_disconnect_read;
+ f_ops->write = snd_disconnect_write;
f_ops->poll = snd_disconnect_poll;
+ f_ops->unlocked_ioctl = snd_disconnect_ioctl;
+#ifdef CONFIG_COMPAT
+ f_ops->compat_ioctl = snd_disconnect_ioctl;
+#endif
+ f_ops->mmap = snd_disconnect_mmap;
+ f_ops->fasync = snd_disconnect_fasync;
s_f_ops->next = card->s_f_ops;
card->s_f_ops = s_f_ops;