proc/task_mmu: change proc_get_vma() to stop returning gate VMA at the end

proc_get_vma() returning gate VMA at the end is desirable for the its
current m_start/m_next callers, as they need to report a gate VMA at the
end of the address space.  This behavior is very specific to these callers
and makes proc_get_vma() hard to use for other purposes.

Move this usage-specific behavior into the callers themselves so that
proc_get_vma() returns either a valid VMA, an error or a NULL when no more
VMAs are available.  This makes it more generic, simpler and usable in the
later patches.

Link: https://lore.kernel.org/20260918153318.758387-6-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett (Oracle) <liam@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Usama Arif <usama.arif@linux.dev>
Cc: Vlastimil Babka <vbabka@kernel.org>

0 files changed, 0 insertions, 0 deletions