On Thu, Aug 17, 2017 at 06:08:12PM +0200, Jan Kara wrote:
> Pretty crude for now...
>
> Signed-off-by: Jan Kara <jack@xxxxxxx>
> ---
> fs/ext4/file.c | 2 ++
> include/linux/mm.h | 1 +
> include/linux/mman.h | 3 ++-
> include/uapi/asm-generic/mman.h | 1 +
> mm/mmap.c | 5 +++++
> 5 files changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index f84bb29e941e..850037e140d7 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -340,6 +340,8 @@ static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
> vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
> } else {
> vma->vm_ops = &ext4_file_vm_ops;
> + if (vma->vm_flags & VM_SYNC)
> + return -EOPNOTSUPP;
> }
So each mmap instance would need to reject the flag explicitly?
Or do I misunderstand this VM_SYNC flag?
