Hi Chao,
On Thu, Aug 05, 2021 at 11:01:43AM +0800, Chao Yu wrote:
> On 2021/8/5 8:36, Gao Xiang wrote:
> > DAX is quite useful for some VM use cases in order to save guest
> > memory extremely with minimal lightweight EROFS.
> >
> > In order to prepare for such use cases, add preliminary dax support
> > for non-tailpacking regular files for now.
> >
> > Tested with the DRAM-emulated PMEM and the EROFS image generated by
> > "mkfs.erofs -Enoinline_data enwik9.fsdax.img enwik9"
> >
> > Cc: nvdimm@xxxxxxxxxxxxxxx
> > Cc: linux-fsdevel@xxxxxxxxxxxxxxx
> > Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
> > ---
> > Documentation/filesystems/erofs.rst | 2 +
> > fs/erofs/data.c | 42 +++++++++++++++++++-
> > fs/erofs/inode.c | 4 ++
> > fs/erofs/internal.h | 3 ++
> > fs/erofs/super.c | 59 ++++++++++++++++++++++++++++-
> > 5 files changed, 106 insertions(+), 4 deletions(-)
> >
> > diff --git a/Documentation/filesystems/erofs.rst b/Documentation/filesystems/erofs.rst
> > index 832839fcf4c3..ffd2ae7be511 100644
> > --- a/Documentation/filesystems/erofs.rst
> > +++ b/Documentation/filesystems/erofs.rst
> > @@ -84,6 +84,8 @@ cache_strategy=%s Select a strategy for cached decompression from now on:
> > It still does in-place I/O decompression
> > for the rest compressed physical clusters.
> > ========== =============================================
> > +dax Use direct access (no page cache). See
>
> dax or dax=%s
>
> Otherwise, it looks good to me.
>
> Reviewed-by: Chao Yu <chao@xxxxxxxxxx>
>
Thanks, it originally inherited from filesystems/ext2.rst, I will update
this into
dax, dax={always,never} .....
Since for such image vm-shared memory scenario, no need to add per-file
DAX (at least for now.)
Thanks,
Gao Xiang
> Thanks,
