mm/page_alloc: add an array-based interface to the bulk page allocator

mm/page_alloc: add an array-based interface to the bulk page allocator

The proposed callers for the bulk allocator store pages from the bulk
allocator in an array.  This patch adds an array-based interface to the
API to avoid multiple list iterations.  The page list interface is
preserved to avoid requiring all users of the bulk API to allocate and
manage enough storage to store the pages.

[[email protected]: remove now unused local `allocated']

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mel Gorman <[email protected]>
Reviewed-by: Alexander Lobakin <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Alexander Duyck <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Chuck Lever <[email protected]>
Cc: David Miller <[email protected]>
Cc: Ilias Apalodimas <[email protected]>
Cc: Jesper Dangaard Brouer <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>