To support large folio swapin for shmem in the following patches, add
large folio allocation for the new replacement folio in
shmem_replace_folio().  Moreover large folios occupy N consecutive entries
in the swap cache instead of using multi-index entries like the page
cache, therefore we should replace each consecutive entries in the swap
cache instead of using the shmem_replace_entry().

As well as updating statistics and folio reference count using the number
of pages in the folio.

[baolin.wang@linux.alibaba.com: fix the gfp flag for large folio allocation]
  Link: https://lkml.kernel.org/r/5b1e9c5a-7f61-4d97-a8d7-41767ca04c77@linux.alibaba.com
[baolin.wang@linux.alibaba.com: fix build without CONFIG_TRANSPARENT_HUGEPAGE]
  Link: https://lkml.kernel.org/r/8c03467c-63b2-43b4-9851-222d4188725c@linux.alibaba.com
Link: https://lkml.kernel.org/r/a41138ecc857ef13e7c5ffa0174321e9e2c9970a.1723434324.git.baolin.wang@linux.alibaba.comSigned-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Daniel Gomez <da.gomez@samsung.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>