On Jul 29, 2013, at 8:18 AM, Daniel P. Berrange berrange@redhat.com wrote:
From an API POV, libvirt doesn't need/care about the free space on the volume underlying the filesystem. We actually only care about the free space in a given directory that we're using for disk images. It just happens that we implement this using statvfs() currently. So when I ask for an API above, don't take this to mean I want a statvfs() that knows about sparse volumes. An API or syscall that provides free space for individual directories is fine with me.
Got it. So what's needed is an API that can return available space to user/application, while abstracting whether the limit is a function of btrfs raid peculiarities, thinp overcommitting, or file system quota? And then applications that need to know what this limit is, need to use this new API?
Chris Murphy