From fe9cdf61cc7cb791c40d076503d8910fc0727310 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@gmail.com>
Date: Sun, 22 Sep 2019 17:48:25 -0400
Subject: [PATCH] bcachefs: Count iterators for reflink_p overwrites correctly
In order to avoid trying to allocate too many btree iterators,
bch2_extent_atomic_end() needs to count how many iterators are going to
be needed for insertions and overwrites - but we weren't counting the
iterators for deleting a reflink_v when the refcount goes to 0.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
fs/bcachefs/extents.c | 35 +++++++++++++++++++++++++----------
1 file changed, 25 insertions(+), 10 deletions(-)
diff --git a/fs/bcachefs/extents.c b/fs/bcachefs/extents.c
index 859b1e8206bdb..35abcde4bca2c 100644
--- a/fs/bcachefs/extents.c
+++ b/fs/bcachefs/extents.c
@@ -935,12 +935,13 @@ static unsigned bch2_bkey_nr_alloc_ptrs(struct bkey_s_c k)
return ret;
}
-static int __bch2_extent_atomic_end(struct btree_trans *trans,
- struct bkey_s_c k,
- unsigned offset,
- struct bpos *end,
- unsigned *nr_iters,
- unsigned max_iters)
+static int count_iters_for_insert(struct btree_trans *trans,
+ struct bkey_s_c k,
+ unsigned offset,
+ struct bpos *end,
+ unsigned *nr_iters,
+ unsigned max_iters,
+ bool overwrite)
{
int ret = 0;
@@ -970,6 +971,20 @@ static int __bch2_extent_atomic_end(struct btree_trans *trans,
break;
*nr_iters += 1;
+
+ if (overwrite &&
+ k.k->type == KEY_TYPE_reflink_v) {
+ struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k);
+
+ if (le64_to_cpu(r.v->refcount) == 1)
+ *nr_iters += bch2_bkey_nr_alloc_ptrs(k);
+ }
+
+ /*
+ * if we're going to be deleting an entry from
+ * the reflink btree, need more iters...
+ */
+
if (*nr_iters >= max_iters) {
struct bpos pos = bkey_start_pos(k.k);
pos.offset += r_k.k->p.offset - idx;
@@ -1004,8 +1019,8 @@ int bch2_extent_atomic_end(struct btree_iter *iter,
*end = bpos_min(insert->k.p, b->key.k.p);
- ret = __bch2_extent_atomic_end(trans, bkey_i_to_s_c(insert),
- 0, end, &nr_iters, 10);
+ ret = count_iters_for_insert(trans, bkey_i_to_s_c(insert),
+ 0, end, &nr_iters, 10, false);
if (ret)
return ret;
@@ -1024,8 +1039,8 @@ int bch2_extent_atomic_end(struct btree_iter *iter,
offset = bkey_start_offset(&insert->k) -
bkey_start_offset(k.k);
- ret = __bch2_extent_atomic_end(trans, k, offset,
- end, &nr_iters, 20);
+ ret = count_iters_for_insert(trans, k, offset,
+ end, &nr_iters, 20, true);
if (ret)
return ret;
--
2.30.2