[lustre-devel] [PATCH 19/33] lustre: lmv: treat unknown hash type as sane type

[James Simmons]

From: Lai Siyao <lai.siyao at whamcloud.com>

Directory migration failure may leave directory hash type as
LMV_HASH_TYPE_UNKNOWN|LMV_HASH_FLAG_BAD_TYPE, which should be treated
as sane hash type on existing directories, otherwise such directories
can't be unlinked.

WC-bug-id: https://jira.whamcloud.com/browse/LU-16717
Lustre-commit: 05cdb71ba68135701 ("LU-16717 mdt: treat unknown hash type as sane type")
Signed-off-by: Lai Siyao <lai.siyao at whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/50796
Reviewed-by: Andreas Dilger <adilger at whamcloud.com>
Reviewed-by: Hongchao Zhang <hongchao at whamcloud.com>
Reviewed-by: Oleg Drokin <green at whamcloud.com>
Signed-off-by: James Simmons <jsimmons at infradead.org>
---
 fs/lustre/include/lustre_lmv.h          |  4 ++--
 include/uapi/linux/lustre/lustre_user.h | 10 ++++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/fs/lustre/include/lustre_lmv.h b/fs/lustre/include/lustre_lmv.h
index a2ef550e38d4..5e3dbc52e846 100644
--- a/fs/lustre/include/lustre_lmv.h
+++ b/fs/lustre/include/lustre_lmv.h
@@ -443,7 +443,7 @@ static inline bool lmv_is_sane(const struct lmv_mds_md_v1 *lmv)
 	if (le32_to_cpu(lmv->lmv_stripe_count) == 0)
 		goto insane;
 
-	if (!lmv_is_known_hash_type(le32_to_cpu(lmv->lmv_hash_type)))
+	if (!lmv_is_sane_hash_type(le32_to_cpu(lmv->lmv_hash_type)))
 		goto insane;
 
 	return true;
@@ -465,7 +465,7 @@ static inline bool lmv_is_sane2(const struct lmv_mds_md_v1 *lmv)
 	if (le32_to_cpu(lmv->lmv_stripe_count) == 0)
 		goto insane;
 
-	if (!lmv_is_known_hash_type(le32_to_cpu(lmv->lmv_hash_type)))
+	if (!lmv_is_sane_hash_type(le32_to_cpu(lmv->lmv_hash_type)))
 		goto insane;
 
 	return true;
diff --git a/include/uapi/linux/lustre/lustre_user.h b/include/uapi/linux/lustre/lustre_user.h
index c098d119f18c..4b49bb9c370a 100644
--- a/include/uapi/linux/lustre/lustre_user.h
+++ b/include/uapi/linux/lustre/lustre_user.h
@@ -794,6 +794,16 @@ static inline bool lmv_is_known_hash_type(__u32 type)
 
 #define LMV_HASH_FLAG_KNOWN		0xbe000000
 
+/* migration failure may leave hash type as
+ * LMV_HASH_TYPE_UNKNOWN|LMV_HASH_FLAG_BAD_TYPE, which should be treated as
+ * sane, so such directory can be accessed (resume migration or unlink).
+ */
+static inline bool lmv_is_sane_hash_type(__u32 type)
+{
+	return lmv_is_known_hash_type(type) ||
+	       type == (LMV_HASH_TYPE_UNKNOWN | LMV_HASH_FLAG_BAD_TYPE);
+}
+
 /* both SPLIT and MIGRATION are set for directory split */
 static inline bool lmv_hash_is_splitting(__u32 hash)
 {
-- 
2.39.3