On Mon, Mar 05, 2007 at 07:15:33AM -0800, Ulrich Drepper wrote:

Theodore Tso wrote:

quoted

Given that glibc already has to support this for older kernels, I
would argue that there's no point putting in generic support for
filesystem that can't support a more advanced way of doing things.

Well, I'm sure the kernel can do better than the code we have in libc
now.  The kernel has access to the bitmasks which say which blocks have
already been allocated.

The layer of the kernel where a totally generic fallback would be
implemented does not have access to this information.  We could do
a mostly generic helper for block filesystems that allows to implement
fallocate this way without a lot of their own code.