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
