Add dax operation zero_page_range for dcssblk driver. CC: linux-s390@xxxxxxxxxxxxxxx Suggested-by: Christoph Hellwig <hch@xxxxxxxxxxxxx> Signed-off-by: Vivek Goyal <vgoyal@xxxxxxxxxx> --- drivers/s390/block/dcssblk.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c index 63502ca537eb..331abab5d066 100644 --- a/drivers/s390/block/dcssblk.c +++ b/drivers/s390/block/dcssblk.c @@ -57,11 +57,28 @@ static size_t dcssblk_dax_copy_to_iter(struct dax_device *dax_dev, return copy_to_iter(addr, bytes, i); } +static int dcssblk_dax_zero_page_range(struct dax_device *dax_dev, u64 offset, + size_t len) +{ + long rc; + void *kaddr; + pgoff_t pgoff = offset >> PAGE_SHIFT; + unsigned page_offset = offset_in_page(offset); + + rc = dax_direct_access(dax_dev, pgoff, 1, &kaddr, NULL); + if (rc < 0) + return rc; + memset(kaddr + page_offset, 0, len); + dax_flush(dax_dev, kaddr + page_offset, len); + return 0; +} + static const struct dax_operations dcssblk_dax_ops = { .direct_access = dcssblk_dax_direct_access, .dax_supported = generic_fsdax_supported, .copy_from_iter = dcssblk_dax_copy_from_iter, .copy_to_iter = dcssblk_dax_copy_to_iter, + .zero_page_range = dcssblk_dax_zero_page_range, }; struct dcssblk_dev_info { -- 2.20.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel