huge tmpfs: revert shmem's use of transhuge_vma_enabled()

5.14 commit e6be37b2e7bd ("mm/huge_memory.c: add missing read-only THP
checking in transparent_hugepage_enabled()") added transhuge_vma_enabled()
as a wrapper for two very different checks (one check is whether the app
has marked its address range not to use THPs, the other check is whether
the app is running in a hierarchy that has been marked never to use THPs).
shmem_huge_enabled() prefers to show those two checks explicitly, as
before.

Link: https://lkml.kernel.org/r/45e5338-18d-c6f9-c17e-34f510bc1728@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/shmem.c b/mm/shmem.c
index 9403048f4ee10417baa8a269ca7164465ac631bd..43cb1a99f3ce15c0c8a8bc0c276b6c2b59a6f57c 100644 (file)
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -3987,7 +3987,8 @@ bool shmem_huge_enabled(struct vm_area_struct *vma)
        loff_t i_size;
        pgoff_t off;
 
-       if (!transhuge_vma_enabled(vma, vma->vm_flags))
+       if ((vma->vm_flags & VM_NOHUGEPAGE) ||
+           test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
                return false;
        if (shmem_huge == SHMEM_HUGE_FORCE)
                return true;