The first_index/last_index parameters in zap_details are actually only
used in unmap_mapping_range_tree().  At the meantime, this function is
only called by unmap_mapping_pages() once.

Instead of passing these two variables through the whole stack of page
zapping code, remove them from zap_details and let them simply be
parameters of unmap_mapping_range_tree(), which is inlined.

Link: https://lkml.kernel.org/r/20210915181535.11238-1-peterx@redhat.comSigned-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Liam Howlett <liam.howlett@oracle.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>