bcachefs: Fix bch2_btree_iter_rewind()

We'd hit a BUG() when rewinding at the start of the btree on btrees with
snapshots.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index 22419929ac1b71dfbbb5c563bbaf6901e30b4bf4..745bf48241fd5b61bbce3504a807e3172b8eefd3 100644 (file)
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -1622,7 +1622,9 @@ inline bool bch2_btree_iter_advance(struct btree_iter *iter)
 inline bool bch2_btree_iter_rewind(struct btree_iter *iter)
 {
        struct bpos pos = bkey_start_pos(&iter->k);
-       bool ret = bpos_cmp(pos, POS_MIN) != 0;
+       bool ret = (iter->flags & BTREE_ITER_ALL_SNAPSHOTS
+                   ? bpos_cmp(pos, POS_MIN)
+                   : bkey_cmp(pos, POS_MIN)) != 0;
 
        if (ret && !(iter->flags & BTREE_ITER_IS_EXTENTS))
                pos = bkey_predecessor(iter, pos);