[PATCH 1/3] shmem: fix tmpfs to handle the huge= option properly

[Hugh Dickins]

From: Toshi Kani 

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 
Signed-off-by: Toshi Kani 
Acked-by: Kirill A. Shutemov 
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: Hugh Dickins 
---

 mm/shmem.c |2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- 4.8-rc7/mm/shmem.c  2016-08-14 20:17:02.388843463 -0700
+++ linux/mm/shmem.c2016-09-22 19:41:29.057848626 -0700
@@ -1980,7 +1980,7 @@ unsigned long shmem_get_unmapped_area(st
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;
}
 

[PATCH 1/3] shmem: fix tmpfs to handle the huge= option properly

[Hugh Dickins]

From: Toshi Kani 

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 
Signed-off-by: Toshi Kani 
Acked-by: Kirill A. Shutemov 
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: Hugh Dickins 
---

 mm/shmem.c |2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- 4.8-rc7/mm/shmem.c  2016-08-14 20:17:02.388843463 -0700
+++ linux/mm/shmem.c2016-09-22 19:41:29.057848626 -0700
@@ -1980,7 +1980,7 @@ unsigned long shmem_get_unmapped_area(st
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;
}