1 files changed, 24 insertions, 11 deletions

diff --git a/libbcachefs/super-io.c b/libbcachefs/super-io.c
index 550a140..b36cfdf 100644
--- a/libbcachefs/super-io.c
+++ b/libbcachefs/super-io.c
@@ -949,6 +949,25 @@ int bch2_fs_mark_dirty(struct bch_fs *c)
 	return ret;
 }
 
+static void
+entry_init_u64s(struct jset_entry *entry, unsigned u64s)
+{
+	memset(entry, 0, u64s * sizeof(u64));
+
+	/*
+	 * The u64s field counts from the start of data, ignoring the shared
+	 * fields.
+	 */
+	entry->u64s = u64s - 1;
+}
+
+static void
+entry_init_size(struct jset_entry *entry, size_t size)
+{
+	unsigned u64s = DIV_ROUND_UP(size, sizeof(u64));
+	entry_init_u64s(entry, u64s);
+}
+
 struct jset_entry *
 bch2_journal_super_entries_add_common(struct bch_fs *c,
 				      struct jset_entry *entry,
@@ -963,7 +982,7 @@ bch2_journal_super_entries_add_common(struct bch_fs *c,
 	     r < c->btree_roots + BTREE_ID_NR;
 	     r++)
 		if (r->alive) {
-			entry->u64s	= r->key.u64s;
+			entry_init_u64s(entry, r->key.u64s + 1);
 			entry->btree_id	= r - c->btree_roots;
 			entry->level	= r->level;
 			entry->type	= BCH_JSET_ENTRY_btree_root;
@@ -988,8 +1007,7 @@ bch2_journal_super_entries_add_common(struct bch_fs *c,
 		struct jset_entry_usage *u =
 			container_of(entry, struct jset_entry_usage, entry);
 
-		memset(u, 0, sizeof(*u));
-		u->entry.u64s	= DIV_ROUND_UP(sizeof(*u), sizeof(u64)) - 1;
+		entry_init_size(entry, sizeof(*u));
 		u->entry.type	= BCH_JSET_ENTRY_usage;
 		u->entry.btree_id = FS_USAGE_INODES;
 		u->v		= cpu_to_le64(c->usage_base->nr_inodes);
@@ -1001,8 +1019,7 @@ bch2_journal_super_entries_add_common(struct bch_fs *c,
 		struct jset_entry_usage *u =
 			container_of(entry, struct jset_entry_usage, entry);
 
-		memset(u, 0, sizeof(*u));
-		u->entry.u64s	= DIV_ROUND_UP(sizeof(*u), sizeof(u64)) - 1;
+		entry_init_size(entry, sizeof(*u));
 		u->entry.type	= BCH_JSET_ENTRY_usage;
 		u->entry.btree_id = FS_USAGE_KEY_VERSION;
 		u->v		= cpu_to_le64(atomic64_read(&c->key_version));
@@ -1014,8 +1031,7 @@ bch2_journal_super_entries_add_common(struct bch_fs *c,
 		struct jset_entry_usage *u =
 			container_of(entry, struct jset_entry_usage, entry);
 
-		memset(u, 0, sizeof(*u));
-		u->entry.u64s	= DIV_ROUND_UP(sizeof(*u), sizeof(u64)) - 1;
+		entry_init_size(entry, sizeof(*u));
 		u->entry.type	= BCH_JSET_ENTRY_usage;
 		u->entry.btree_id = FS_USAGE_RESERVED;
 		u->entry.level	= i;
@@ -1030,10 +1046,7 @@ bch2_journal_super_entries_add_common(struct bch_fs *c,
 		struct jset_entry_data_usage *u =
 			container_of(entry, struct jset_entry_data_usage, entry);
 
-		int u64s = DIV_ROUND_UP(sizeof(*u) + e->nr_devs,
-					sizeof(u64)) - 1;
-		memset(u, 0, u64s * sizeof(u64));
-		u->entry.u64s	= u64s;
+		entry_init_size(entry, sizeof(*u) + e->nr_devs);
 		u->entry.type	= BCH_JSET_ENTRY_data_usage;
 		u->v		= cpu_to_le64(c->usage_base->replicas[i]);
 		memcpy(&u->r, e, replicas_entry_bytes(e));