[PATCH v2 4/4] btrfs-progs: volumes: Use new raid5_gen_result to calculate raid5 parity

[Qu Wenruo <quwenruo@cn.fujitsu.com>]

Use thew raid5_gen_result() function to calculate raid5 parity.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
Changelog:
v2:
  None
---
 volumes.c | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/volumes.c b/volumes.c
index 70d8940..6d7adef 100644
--- a/volumes.c
+++ b/volumes.c
@@ -2133,7 +2133,6 @@ int write_raid56_with_parity(struct btrfs_fs_info *info,
 {
 	struct extent_buffer **ebs, *p_eb = NULL, *q_eb = NULL;
 	int i;
-	int j;
 	int ret;
 	int alloc_size = eb->len;
 	void **pointers;
@@ -2188,18 +2187,12 @@ int write_raid56_with_parity(struct btrfs_fs_info *info,
 		raid6_gen_syndrome(multi->num_stripes, stripe_len, pointers);
 	} else {
 		ebs[multi->num_stripes - 1] = p_eb;
-		memcpy(p_eb->data, ebs[0]->data, stripe_len);
-		for (j = 1; j < multi->num_stripes - 1; j++) {
-			for (i = 0; i < stripe_len; i += sizeof(u64)) {
-				u64 p_eb_data;
-				u64 ebs_data;
-
-				p_eb_data = get_unaligned_64(p_eb->data + i);
-				ebs_data = get_unaligned_64(ebs[j]->data + i);
-				p_eb_data ^= ebs_data;
-				put_unaligned_64(p_eb_data, p_eb->data + i);
-			}
-		}
+		for (i = 0; i < multi->num_stripes; i++)
+			pointers[i] = ebs[i]->data;
+		ret = raid5_gen_result(multi->num_stripes, stripe_len,
+				       multi->num_stripes - 1, pointers);
+		if (ret < 0)
+			goto out_free_split;
 	}
 
 	for (i = 0; i < multi->num_stripes; i++) {
-- 
2.10.1