tools/lib/mm: add shared file helpers

Move read_file(), write_file(), read_num(), write_num() and
write_num_ignore_einval() out of tools/testing/selftests/mm/vm_util.c into
a new shared helper under tools/lib/mm/.

These helpers are used by mm selftests today and will also be needed by
shared hugepage helpers in subsequent patches.  Move them to a generic
location so they can be reused outside selftests as well.

Keep the helpers exposed to mm selftests through vm_util.h by including
the new shared header there, and link the new helper into the selftests/mm
build.

Update the explicit x86 protection_keys 32-bit and 64-bit build rules to
preserve prerequisite paths, now that file_utils.c is built from
tools/lib/mm.

Add tools/lib/mm/ to the MEMORY MANAGEMENT - MISC entry in MAINTAINERS.

Link: https://lore.kernel.org/20260918112234.195857-3-sarthak.sharma@arm.com
Signed-off-by: Sarthak Sharma <sarthak.sharma@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Tested-by: Muhammad Usama Anjum <usama.anjum@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nico Pache <npache@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Zi Yan <ziy@nvidia.com>

0 files changed, 0 insertions, 0 deletions