On Mon, Aug 11, 2014 at 04:30:19PM -0400, John Ferlan wrote:
Currently the safezero() function uses build conditionals to choose either the posix_fallocate() or mmap() with a fallback to safewrite() in order to preallocate a file.
This patch will modify the logic in order to allow fallbacks in the event that posix_fallocate() or the ftruncate()and mmap() doesn't work properly. The fallback will be to use the slow safewrite of zero filled buffers to the file.
Have you actually encountered failing of posix_fallocate() in the real world ? It is supposed to automatically fallback to the equivalent of writing zeros if the filesystem / kernel does not support it, so we should not have todo runtime fallback ourselves. The existance of fallback is the main distinction between the posix_fallocate() and fallocate() system calls. 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 :|