Re: [libvirt] [PATCH 2/3] fdstream: introduce virFDStreamOpenBlockDevice

On Fri, Aug 15, 2014 at 12:44:21PM +0400, Roman Bogorodskiy wrote: > virStorageBackendVolDownloadLocal and virStorageBackendVolUploadLocal > use virFDStreamOpenFile function to work with the volume fd. > > virFDStreamOpenFile calls virFDStreamOpenFileInternal that implements > handling of the non-blocking I/O. If a file is not a character device and > not a fifo, it uses libvirt_iohelper. > > On FreeBSD, it doesn't work as expected because disks are exposed as > character devices. Why does that cause a problem ? The reason we use iohelper is because POSIX does not have O_NONBLOCK work on plain files, so we need to use the iohelper so that we have a pipe we can set O_NONBLOCK on. If FreeBSD disks are character devices though, O_NONBLOCK should work fine on them avoiding the need for iohelper.

Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|