[PATCH 1/2] shmem: fix tmpfs to handle the huge= option properly

From: Toshi Kani
Date: Fri Sep 09 2016 - 18:25:38 EST

shmem_get_unmapped_area() checks SHMEM_SB(sb)->huge incorrectly,
which leads to a reversed effect of "huge=" mount option.

Fix the check in shmem_get_unmapped_area().

Note, the default value of SHMEM_SB(sb)->huge remains as
SHMEM_HUGE_NEVER. User will need to specify "huge=" option to
enable huge page mappings.

Reported-by: Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx>
Signed-off-by: Toshi Kani <toshi.kani@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
mm/shmem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index fd8b2b5..aec5b49 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1980,7 +1980,7 @@ unsigned long shmem_get_unmapped_area(struct file *file,
return addr;
sb = shm_mnt->mnt_sb;
- if (SHMEM_SB(sb)->huge != SHMEM_HUGE_NEVER)
+ if (SHMEM_SB(sb)->huge == SHMEM_HUGE_NEVER)
return addr;