Messages in this thread | | | Subject | Re: [RFC PATCH v2 0/7] xfs: reflink & dedupe for fsdax (read/write path). | From | Shiyang Ruan <> | Date | Thu, 31 Oct 2019 12:54:54 +0800 |
| |
On 10/30/19 7:48 PM, Goldwyn Rodrigues wrote: > On 12:13 30/10, Shiyang Ruan wrote: >> This patchset aims to take care of this issue to make reflink and dedupe >> work correctly (actually in read/write path, there still has some problems, >> such as the page->mapping and page->index issue, in mmap path) in XFS under >> fsdax mode. > > Have you managed to solve the problem of multi-mapped pages? I don't > think we can include this until we solve that problem. This is the > problem I faced when I was doing the btrfs dax support.
That problem still exists, didn't be solved in this patchset. But I am also looking into it. As you know, it's a bit difficult.
Since the iomap for cow is merged in for-next tree, I think it's time to update this in order to get some comments.
> > Suppose there is an extent shared with multiple files. You map data for > both files. Which inode should page->mapping->host (precisely > page->mapping) point to? As Dave pointed out, this needs to be fixed at > the mm level, and will not only benefit dax with CoW but other > areas such as overlayfs and possibly containers.
Yes, I will try to figure out a solution. >
-- Thanks, Shiyang Ruan.
| |