Re: [f2fs-dev] [PATCH 2/2] f2fs: allow dio read for LFS mode

From: Jaegeuk Kim
Date: Fri Nov 25 2016 - 13:14:19 EST


On Fri, Nov 25, 2016 at 11:54:43PM +0800, Chao Yu wrote:
> On 2016/11/12 5:03, Jaegeuk Kim wrote:
> > We can allow dio reads for LFS mode, while doing buffered writes for dio writes.
> >
> > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > ---
> > fs/f2fs/data.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> > index ca53da5..996b9ae 100644
> > --- a/fs/f2fs/data.c
> > +++ b/fs/f2fs/data.c
> > @@ -1732,7 +1732,7 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
> >
> > if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
> > return 0;
> > - if (test_opt(F2FS_I_SB(inode), LFS))
> > + if (rw == WRITE && test_opt(F2FS_I_SB(inode), LFS))
>
> For LFS mode, we must disallow any IPU in main area including direct write,
> instead of both direct read and write, so this patch relieves the restriction?

Yup.

>
> IIUC, please add:
>
> Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
>
> Thanks,
>
> > return 0;
> >
> > trace_f2fs_direct_IO_enter(inode, offset, count, rw);
> >