path: root/mm
diff options
authorOmar Sandoval <osandov@fb.com>2018-10-26 15:10:55 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-10-26 16:38:15 -0700
commitaa8aa8a331d27fcef3e60dabb918eb8c5c9a2ad9 (patch)
tree5f200509a0bcf548126fc9abe385637924555853 /mm
parentbc4ae27d817a4e92071ef67cb6368120cfabe7ec (diff)
mm: export add_swap_extent()
Btrfs currently does not support swap files because swap's use of bmap does not work with copy-on-write and multiple devices. See 35054394c4b3 ("Btrfs: stop providing a bmap operation to avoid swapfile corruptions"). However, the swap code has a mechanism for the filesystem to manually add swap extents using add_swap_extent() from the ->swap_activate() aop. iomap has done this since 67482129cdab ("iomap: add a swapfile activation function"). Btrfs will do the same in a later patch, so export add_swap_extent(). Link: http://lkml.kernel.org/r/bb1208575e02829aae51b538709476964f97b1ea.1536704650.git.osandov@fb.com Signed-off-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: David Sterba <dsterba@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
1 files changed, 1 insertions, 0 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c
index f0c7e4c11bab..644f746e167a 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2354,6 +2354,7 @@ add_swap_extent(struct swap_info_struct *sis, unsigned long start_page,
list_add_tail(&new_se->list, &sis->first_swap_extent.list);
return 1;
* A `swap extent' is a simple thing which maps a contiguous range of pages