The __NR_statfs64 syscall is supported on all architectures but
aarch64, mips64, riscv64, and x86_64. And newer ABIs also uses
the new statfs64 interface (where the struct size is used as
second argument).
So the default implementation now uses:
1. __NR_statfs64 for non-LFS call and handle overflow directly
There is no need to handle __NR_statfs since all architectures
that only support are LFS only.
2. __NR_statfs if defined or __NR_statfs64 otherwise for LFS
call.
Alpha is the only outlier, since it is a 64-bit architecture which
provides non-LFS interface and only provides __NR_statfs64 on
newer kernels (v5.1+).
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
