Josef Bacik <jo...@redhat.com> wrote: >On Sun, Dec 13, 2009 at 12:29:03AM +0000, Jason White wrote: >> I am testing a Btrfs root file system with Debian (kernel 2.6.32) under KVM. >> >> ja...@vrtl:~$ touch testfile >> ja...@vrtl:~$ cp --reflink testfile /tmp >> cp: failed to clone `/tmp/testfile': Invalid argument >> >> This is with GNU Coreutils 8.0 taken from debian Sid. >> >> Is this a Coreutils issue, a Btrfs problem or something in my local >> configuration? >> > >Try using bcp, if that works then its likely a problem with coreutils.
After reporting this to Debian and engaging on follow-up discussion, it turns out that bcp copies the data if the ioctl() call to clone the file fails, as can be seen from the Python code (which I should have read, but didn't...). Unfortunately the ioctl() call is failing both in bcp and in cp --reflink. Here's partial strace output from the latter. cp --reflink testfile testfile2 open("testfile", O_RDONLY) = 3 fstat(3, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0 open("testfile2", O_WRONLY|O_CREAT|O_EXCL, 0644) = 4 fstat(4, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0 ioctl(4, 0x40049409, 0x3) = -1 EINVAL (Invalid argument) Kernel 2.6.32 (debian Sid), x86-64 architecture. Suggestions welcome. Debian bug report: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=561225 -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org