implement O_NONBLOCK for /proc/xen/xenbus

This patch implements O_NONBLOCK for /proc/xen/xenbus.  It is a simple
matter of returning -EAGAIN instead of waiting on a queue.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This commit is contained in:
Paolo Bonzini 2010-06-23 18:30:15 +02:00 committed by Jeremy Fitzhardinge
parent 4c31a78114
commit 6280f190da

View File

@ -122,6 +122,9 @@ static ssize_t xenbus_file_read(struct file *filp,
mutex_lock(&u->reply_mutex);
while (list_empty(&u->read_buffers)) {
mutex_unlock(&u->reply_mutex);
if (filp->f_flags & O_NONBLOCK)
return -EAGAIN;
ret = wait_event_interruptible(u->read_waitq,
!list_empty(&u->read_buffers));
if (ret)