mm: move drivers/char/mem.c to mm/char-mem.c

The memory character driver implements several mm-specific features and is
always compiled into the kernel, so move it to mm/ where it belongs.

Among other things the driver implements /dev/mem which provides raw access
to physical memory, and /dev/zero which either allows mapping of a shmem
region (if mapped with MAP_SHARED) or, uniquely, anonymous memory (if
mapped MAP_PRIVATE).

This change lays the foundations to allow MAP_PRIVATE-/dev/zero to be
mapped precisely the same as anonymous memory is mapped as currently it is
an edge case within mm.

Also update a couple of comments that reference 'drivers/char/mem.c' to
reference 'mm/char-mem.c'.

Link: https://lore.kernel.org/20260926-map-private-dev-zero-v3-1-d4781e84ccfc@kernel.org
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Jan Kara <jack@suse.cz>

0 files changed, 0 insertions, 0 deletions