On 2021/9/16 14:16, Christoph Hellwig wrote:
On Wed, Sep 15, 2021 at 06:44:58PM +0800, Shiyang Ruan wrote:+ rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL); + if (rc < 0) + goto out; + memset(kaddr + offset, 0, size); + if (srcmap->addr != IOMAP_HOLE && srcmap->addr != iomap->addr) {Should we also check that ->dax_dev for iomap and srcmap are different first to deal with case of file system with multiple devices?
I have not thought of this case. Isn't it possible to CoW between different devices?
-- Thanks, Ruan
Otherwise looks good: Reviewed-by: Christoph Hellwig <[email protected]>

