[RFC v2 25/43] mm: shmem: prevent swapping of PKRAM-enabled tmpfs pages

[Anthony Yznaga]

Work around the limitation that shmem pages must be in memory in order
to be preserved by preventing them from being swapped out in the first
place.  Do this by marking shmem pages associated with a PKRAM node
as unevictable.

Signed-off-by: Anthony Yznaga <anthony.yznaga at oracle.com>
---
 mm/shmem.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/shmem.c b/mm/shmem.c
index c1c5760465f2..8dfe80aeee97 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2400,6 +2400,8 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
 		INIT_LIST_HEAD(&info->swaplist);
 		simple_xattrs_init(&info->xattrs);
 		cache_no_acl(inode);
+		if (sbinfo->pkram)
+			mapping_set_unevictable(inode->i_mapping);
 
 		switch (mode & S_IFMT) {
 		default:
-- 
1.8.3.1