[03/30] block: Use kmemdup rather than duplicating its implementation

Commit Message

Fuqian Huang July 3, 2019, 1:13 p.m. UTC

kmemdup is introduced to duplicate a region of memory in a neat way.
Rather than kmalloc/kzalloc + memset, which the programmer needs to
write the size twice (sometimes lead to mistakes), kmemdup improves
readability, leads to smaller code and also reduce the chances of mistakes.
Suggestion to use kmemdup rather than using kmalloc/kzalloc + memset.

Signed-off-by: Fuqian Huang <[e-mail]>
---
 drivers/block/rbd.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Patch

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index e5009a34f9c2..47ad3772dc58 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1068,7 +1068,7 @@  static int rbd_header_from_disk(struct rbd_device *rbd_dev,
 
 		if (snap_names_len > (u64)SIZE_MAX)
 			goto out_2big;
-		snap_names = kmalloc(snap_names_len, GFP_KERNEL);
+		snap_names = kmemdup(&ondisk->snaps[snap_count], snap_names_len, GFP_KERNEL);
 		if (!snap_names)
 			goto out_err;
 
@@ -1088,7 +1088,6 @@  static int rbd_header_from_disk(struct rbd_device *rbd_dev,
 		 * snap_names_len bytes beyond the end of the
 		 * snapshot id array, this memcpy() is safe.
 		 */
-		memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
 		snaps = ondisk->snaps;
 		for (i = 0; i < snap_count; i++) {
 			snapc->snaps[i] = le64_to_cpu(snaps[i].id);