mm: split a folio in minimum folio order chunks

split_folio() and split_folio_to_list() assume order 0, to support
minorder for non-anonymous folios, we must expand these to check the
folio mapping order and use that.

Set new_order to be at least minimum folio order if it is set in
split_huge_page_to_list() so that we can maintain minimum folio order
requirement in the page cache.

Update the debugfs write files used for testing to ensure the order
is respected as well. We simply enforce the min order when a file
mapping is used.

Signed-off-by: Luis Chamberlain <[email protected]>
Signed-off-by: Pankaj Raghav <[email protected]>
Link: https://lore.kernel.org/r/[email protected] # folded fix
Link: https://lore.kernel.org/r/[email protected]
Tested-by: David Howells <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Zi Yan <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

0 files changed, 0 insertions, 0 deletions