[RFC PATCH 1/4] fs/iomap: Introduce src_addr for COW in fsdax mode.
When using reflink, coping the source blocks before writing data
into new allocated blocks is required. In fsdax mode, we need a source
blocks' start address to handle the COW operation.
Signed-off-by: Shiyang Ruan <ruansy.fnst(a)cn.fujitsu.com>
---
include/linux/iomap.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/include/linux/iomap.h b/include/linux/iomap.h
index 0fefb5455bda..3b3aec2311c5 100644
--- a/include/linux/iomap.h
+++ b/include/linux/iomap.h
@@ -61,6 +61,10 @@ struct iomap {
u16 flags; /* flags for mapping */
struct block_device *bdev; /* block device for I/O */
struct dax_device *dax_dev; /* dax_dev for dax operations */
+ u64 src_addr; /* disk offset of mapping, bytes,
+ * the source blocks' start address
+ * for cow in dax
+ */
void *inline_data;
void *private; /* filesystem private */
--
2.17.0