bcachefs: Fix btree updates when mixing cached and non cached iterators

There was a bug where bch2_trans_update() would incorrectly delete a
pending update where the new update did not actually overwrite the
existing update, because we were incorrectly using BTREE_ITER_TYPE when
sorting pending btree updates.

This affects the pending patch to use cached iterators for inode
updates.

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

diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c
index 90d884b18b70d0bf8dc11cd46d61f4b5e7b4c341..c503d76bab3ba3a16906aefc6f45b21f19526a88 100644 (file)
--- a/fs/bcachefs/btree_cache.c
+++ b/fs/bcachefs/btree_cache.c
@@ -949,7 +949,7 @@ struct btree *bch2_btree_node_get_sibling(struct bch_fs *c,
                 * holding other locks that would cause us to deadlock:
                 */
                trans_for_each_iter(trans, linked)
-                       if (btree_iter_cmp(iter, linked) < 0)
+                       if (btree_iter_lock_cmp(iter, linked) < 0)
                                __bch2_btree_iter_unlock(linked);
 
                if (sib == btree_prev_sib)

diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index 7501556c0988f6d6e922bf81bef5987aa2a405ae..b561d0353d77bd08008cf044e95e4aa77ede06cd 100644 (file)
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -1104,7 +1104,7 @@ retry_all:
                sorted[nr_sorted++] = iter->idx;
 
 #define btree_iter_cmp_by_idx(_l, _r)                          \
-               btree_iter_cmp(&trans->iters[_l], &trans->iters[_r])
+               btree_iter_lock_cmp(&trans->iters[_l], &trans->iters[_r])
 
        bubble_sort(sorted, nr_sorted, btree_iter_cmp_by_idx);
 #undef btree_iter_cmp_by_idx

diff --git a/fs/bcachefs/btree_iter.h b/fs/bcachefs/btree_iter.h
index bd9ec3ec9a92a2809128f6ae799dfeae44bc9ca9..f80e09255f68cf4a1dc6e0fd8ee93403154ea4bd 100644 (file)
--- a/fs/bcachefs/btree_iter.h
+++ b/fs/bcachefs/btree_iter.h
@@ -177,8 +177,9 @@ void bch2_btree_iter_set_pos_same_leaf(struct btree_iter *, struct bpos);
 void __bch2_btree_iter_set_pos(struct btree_iter *, struct bpos, bool);
 void bch2_btree_iter_set_pos(struct btree_iter *, struct bpos);
 
-static inline int btree_iter_cmp(const struct btree_iter *l,
-                                const struct btree_iter *r)
+/* Sort order for locking btree iterators: */
+static inline int btree_iter_lock_cmp(const struct btree_iter *l,
+                                     const struct btree_iter *r)
 {
        return   cmp_int(l->btree_id, r->btree_id) ?:
                -cmp_int(btree_iter_type(l), btree_iter_type(r)) ?:

diff --git a/fs/bcachefs/btree_update_leaf.c b/fs/bcachefs/btree_update_leaf.c
index 9c33a8be2c580517dfb8f760dbe07a2397a6a42a..839dba099cac25f303987d8ba297c88417453764 100644 (file)
--- a/fs/bcachefs/btree_update_leaf.c
+++ b/fs/bcachefs/btree_update_leaf.c
@@ -690,6 +690,13 @@ bch2_trans_commit_get_rw_cold(struct btree_trans *trans)
        return 0;
 }
 
+static inline int btree_iter_pos_cmp(const struct btree_iter *l,
+                                    const struct btree_iter *r)
+{
+       return   cmp_int(l->btree_id, r->btree_id) ?:
+                bkey_cmp(l->pos, r->pos);
+}
+
 static void bch2_trans_update2(struct btree_trans *trans,
                               struct btree_iter *iter,
                               struct bkey_i *insert)
@@ -707,12 +714,12 @@ static void bch2_trans_update2(struct btree_trans *trans,
        iter->flags |= BTREE_ITER_KEEP_UNTIL_COMMIT;
 
        trans_for_each_update2(trans, i) {
-               if (btree_iter_cmp(n.iter, i->iter) == 0) {
+               if (btree_iter_pos_cmp(n.iter, i->iter) == 0) {
                        *i = n;
                        return;
                }
 
-               if (btree_iter_cmp(n.iter, i->iter) <= 0)
+               if (btree_iter_pos_cmp(n.iter, i->iter) <= 0)
                        break;
        }
 
@@ -996,7 +1003,7 @@ int bch2_trans_update(struct btree_trans *trans, struct btree_iter *iter,
         * Pending updates are kept sorted: first, find position of new update:
         */
        trans_for_each_update(trans, i)
-               if (btree_iter_cmp(iter, i->iter) <= 0)
+               if (btree_iter_pos_cmp(iter, i->iter) <= 0)
                        break;
 
        /*