To be consistent with the rest of the code the sysfs helper should
return the -errno instead of passing -1 from various syscalls. Update
callers that relied on -1 as the invalid file descriptor.
Signed-off-by: David Sterba <dsterba@suse.com>
strtoull may return the boundary values, if the callers could expect
that and verify it then the errno must be reset before the call.
Signed-off-by: David Sterba <dsterba@suse.com>
In some places we want to read a single u64 value from a sysfs path, or
from fsid directory. Add helpers that do that in one go.
Signed-off-by: David Sterba <dsterba@suse.com>
The sysfs could use more convenience helpers so move the current code to
own file before adding more helpers.
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba