tracing/probes: Add fetch{,_size} member into deref fetch method
tracing/probes: Add fetch{,_size} member into deref fetch method

The deref fetch methods access a memory region but it assumes that
it's a kernel memory since uprobes does not support them.

Add ->fetch and ->fetch_size member in order to provide a proper
access methods for supporting uprobes.

Acked-by: Masami Hiramatsu <60fcdccfd958d359debfe6e6e7417cd7f1aaa9e3@hitachi.com>
Acked-by: Oleg Nesterov <20b70f0af00562e63758b9ee42012ecc96c58590@redhat.com>
Cc: Srikar Dronamraju <1f69195f6d934d4caf5816234bde319316df237e@linux.vnet.ibm.com>
Cc: zhangwei(Jovi) <a8ae8cb0c5ce7eeda1b4de6b4b82210f652e86b4@huawei.com>
Cc: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@ghostprotocols.net>
Signed-off-by: Hyeoncheol Lee <21843ff21999b47c0788d587add85b508a7d5632@lge.com>
[5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org: Split original patch into pieces as requested]
Signed-off-by: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs