From: Darrick J. Wong <djwong@xxxxxxxxxx>
As a minor space optimization, don't store trailing zeroes of merkle
tree blocks to reduce space consumption and copying overhead. This
really only affects the rightmost blocks at each level of the tree.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
fs/xfs/xfs_verity.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/fs/xfs/xfs_verity.c b/fs/xfs/xfs_verity.c
index 32891ae42c47..abd95bc1ba6e 100644
--- a/fs/xfs/xfs_verity.c
+++ b/fs/xfs/xfs_verity.c
@@ -622,11 +622,6 @@ xfs_verity_read_merkle(
if (error)
goto out_new_mk;
- if (!args.valuelen) {
- error = -ENODATA;
- goto out_new_mk;
- }
-
mk = xfs_verity_cache_store(ip, key, new_mk);
if (mk != new_mk) {
/*
@@ -681,6 +676,12 @@ xfs_verity_write_merkle(
.value = (void *)buf,
.valuelen = size,
};
+ const char *p = buf + size - 1;
+
+ /* Don't store trailing zeroes. */
+ while (p >= (const char *)buf && *p == 0)
+ p--;
+ args.valuelen = p - (const char *)buf + 1;
xfs_verity_merkle_key_to_disk(&name, pos);
return xfs_attr_set(&args);
