On Sun, Aug 29, 2021 at 08:25:14PM +0800, Shiyang Ruan wrote:
> Punch hole on a reflinked file needs dax_iomap_cow_copy() too.
> Otherwise, data in not aligned area will be not correct. So, add the
> srcmap to dax_iomap_zero() and replace memset() as dax_iomap_cow_copy().
>
> Signed-off-by: Shiyang Ruan <ruansy.fnst@xxxxxxxxxxx>
> Reviewed-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxx>
> Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
> fs/dax.c | 26 ++++++++++++++++----------
> fs/iomap/buffered-io.c | 4 ++--
> include/linux/dax.h | 3 ++-
> 3 files changed, 20 insertions(+), 13 deletions(-)
>
> diff --git a/fs/dax.c b/fs/dax.c
> index f4acb79cb811..b294900e574e 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -1209,7 +1209,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
> }
> #endif /* CONFIG_FS_DAX_PMD */
>
> -s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap)
> +s64 dax_iomap_zero(loff_t pos, u64 length, const struct iomap *iomap,
> + const struct iomap *srcmap)
We can in fact pass the iomap_iter here as well. (probably as a prep
patch).
> if (page_aligned)
> rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1);
> - else
> + else {
> rc = dax_direct_access(iomap->dax_dev, pgoff, 1, &kaddr, NULL);
I'd clean this up a bit by doing:
id = dax_read_lock();
if (page_aligned) {
rc = dax_zero_page_range(iomap->dax_dev, pgoff, 1);
goto out;
}
// non aligned case here without extra indentation or checks
