From 0a5156334c721295928b4c5f42eabb9c625cd73e Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Sun, 17 Jul 2022 00:44:19 -0400 Subject: [PATCH] bcachefs: Convert erasure coding to for_each_btree_key_commit() The new for_each_btree_key2() macro handles transaction retries, allowing us to avoid nested transactions - which we want to avoid since they're tricky to do completely correctly and upcoming assertions are going to be checking for that. Signed-off-by: Kent Overstreet --- fs/bcachefs/ec.c | 120 ++++++++++++++++++++--------------------------- 1 file changed, 51 insertions(+), 69 deletions(-) diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c index 6ce352c526f0..ed33563d6c28 100644 --- a/fs/bcachefs/ec.c +++ b/fs/bcachefs/ec.c @@ -822,80 +822,62 @@ static void extent_stripe_ptr_add(struct bkey_s_extent e, }; } -static int ec_stripe_update_ptrs(struct bch_fs *c, +static int ec_stripe_update_extent(struct btree_trans *trans, + struct btree_iter *iter, + struct bkey_s_c k, + struct ec_stripe_buf *s, + struct bpos end) +{ + const struct bch_extent_ptr *ptr_c; + struct bch_extent_ptr *ptr, *ec_ptr = NULL; + struct bkey_i *n; + int ret, dev, block; + + if (bkey_cmp(bkey_start_pos(k.k), end) >= 0) + return 1; + + if (extent_has_stripe_ptr(k, s->key.k.p.offset)) + return 0; + + ptr_c = bkey_matches_stripe(&s->key.v, k, &block); + /* + * It doesn't generally make sense to erasure code cached ptrs: + * XXX: should we be incrementing a counter? + */ + if (!ptr_c || ptr_c->cached) + return 0; + + dev = s->key.v.ptrs[block].dev; + + n = bch2_trans_kmalloc(trans, bkey_bytes(k.k)); + ret = PTR_ERR_OR_ZERO(n); + if (ret) + return ret; + + bkey_reassemble(n, k); + + bch2_bkey_drop_ptrs(bkey_i_to_s(n), ptr, ptr->dev != dev); + ec_ptr = (void *) bch2_bkey_has_device(bkey_i_to_s_c(n), dev); + BUG_ON(!ec_ptr); + + extent_stripe_ptr_add(bkey_i_to_s_extent(n), s, ec_ptr, block); + + return bch2_trans_update(trans, iter, n, 0); +} + +static int ec_stripe_update_extents(struct bch_fs *c, struct ec_stripe_buf *s, struct bkey *pos) { - struct btree_trans trans; struct btree_iter iter; struct bkey_s_c k; - struct bkey_s_extent e; - struct bkey_buf sk; - struct bpos next_pos; - int ret = 0, dev, block; - bch2_bkey_buf_init(&sk); - bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0); - - /* XXX this doesn't support the reflink btree */ - - bch2_trans_iter_init(&trans, &iter, BTREE_ID_extents, - bkey_start_pos(pos), - BTREE_ITER_INTENT); -retry: - while (bch2_trans_begin(&trans), - (k = bch2_btree_iter_peek(&iter)).k && - !(ret = bkey_err(k)) && - bkey_cmp(bkey_start_pos(k.k), pos->p) < 0) { - const struct bch_extent_ptr *ptr_c; - struct bch_extent_ptr *ptr, *ec_ptr = NULL; - - if (extent_has_stripe_ptr(k, s->key.k.p.offset)) { - bch2_btree_iter_advance(&iter); - continue; - } - - ptr_c = bkey_matches_stripe(&s->key.v, k, &block); - /* - * It doesn't generally make sense to erasure code cached ptrs: - * XXX: should we be incrementing a counter? - */ - if (!ptr_c || ptr_c->cached) { - bch2_btree_iter_advance(&iter); - continue; - } - - dev = s->key.v.ptrs[block].dev; - - bch2_bkey_buf_reassemble(&sk, c, k); - e = bkey_i_to_s_extent(sk.k); - - bch2_bkey_drop_ptrs(e.s, ptr, ptr->dev != dev); - ec_ptr = (void *) bch2_bkey_has_device(e.s_c, dev); - BUG_ON(!ec_ptr); - - extent_stripe_ptr_add(e, s, ec_ptr, block); - - bch2_btree_iter_set_pos(&iter, bkey_start_pos(&sk.k->k)); - next_pos = sk.k->k.p; - - ret = bch2_btree_iter_traverse(&iter) ?: - bch2_trans_update(&trans, &iter, sk.k, 0) ?: - bch2_trans_commit(&trans, NULL, NULL, - BTREE_INSERT_NOFAIL); - if (!ret) - bch2_btree_iter_set_pos(&iter, next_pos); - if (ret) - break; - } - if (ret == -EINTR) - goto retry; - bch2_trans_iter_exit(&trans, &iter); - - bch2_trans_exit(&trans); - bch2_bkey_buf_exit(&sk, c); - - return ret; + return bch2_trans_run(c, + for_each_btree_key_commit(&trans, iter, + BTREE_ID_extents, bkey_start_pos(pos), + BTREE_ITER_NOT_EXTENTS|BTREE_ITER_INTENT, k, + NULL, NULL, BTREE_INSERT_NOFAIL, + ec_stripe_update_extent(&trans, &iter, k, s, pos->p))); } /* @@ -966,7 +948,7 @@ static void ec_stripe_create(struct ec_stripe_new *s) } for_each_keylist_key(&s->keys, k) { - ret = ec_stripe_update_ptrs(c, &s->new_stripe, &k->k); + ret = ec_stripe_update_extents(c, &s->new_stripe, &k->k); if (ret) { bch_err(c, "error creating stripe: error %i updating pointers", ret); break;