bcachefs: Preserve stripe blockcounts on existing stripes

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

diff --git a/fs/bcachefs/ec.c b/fs/bcachefs/ec.c
index 0d9a27726c058a0e7c00bdb861361f8c546a41d8..d48df42d41e9bc6dc347ec16d67419c514efe658 100644 (file)
--- a/fs/bcachefs/ec.c
+++ b/fs/bcachefs/ec.c
@@ -684,8 +684,8 @@ static void ec_stripe_delete_work(struct work_struct *work)
 /* stripe creation: */
 
 static int ec_stripe_bkey_insert(struct bch_fs *c,
-                                struct ec_stripe_new *s,
-                                struct bkey_i_stripe *stripe)
+                                struct bkey_i_stripe *stripe,
+                                struct disk_reservation *res)
 {
        struct btree_trans trans;
        struct btree_iter *iter;
@@ -726,7 +726,7 @@ found_slot:
 
        bch2_trans_update(&trans, iter, &stripe->k_i, 0);
 
-       ret = bch2_trans_commit(&trans, &s->res, NULL,
+       ret = bch2_trans_commit(&trans, res, NULL,
                                BTREE_INSERT_NOFAIL);
 err:
        bch2_trans_iter_put(&trans, iter);
@@ -740,6 +740,47 @@ err:
        return ret;
 }
 
+static int ec_stripe_bkey_update(struct btree_trans *trans,
+                                struct bkey_i_stripe *new)
+{
+       struct bch_fs *c = trans->c;
+       struct btree_iter *iter;
+       struct bkey_s_c k;
+       const struct bch_stripe *existing;
+       unsigned i;
+       int ret;
+
+       iter = bch2_trans_get_iter(trans, BTREE_ID_EC,
+                                  new->k.p, BTREE_ITER_INTENT);
+       k = bch2_btree_iter_peek_slot(iter);
+       ret = bkey_err(k);
+       if (ret)
+               goto err;
+
+       if (!k.k || k.k->type != KEY_TYPE_stripe) {
+               bch_err(c, "error updating stripe: not found");
+               ret = -ENOENT;
+               goto err;
+       }
+
+       existing = bkey_s_c_to_stripe(k).v;
+
+       if (existing->nr_blocks != new->v.nr_blocks) {
+               bch_err(c, "error updating stripe: nr_blocks does not match");
+               ret = -EINVAL;
+               goto err;
+       }
+
+       for (i = 0; i < new->v.nr_blocks; i++)
+               stripe_blockcount_set(&new->v, i,
+                       stripe_blockcount_get(existing, i));
+
+       bch2_trans_update(trans, iter, &new->k_i, 0);
+err:
+       bch2_trans_iter_put(trans, iter);
+       return ret;
+}
+
 static void extent_stripe_ptr_add(struct bkey_s_extent e,
                                  struct ec_stripe_buf *s,
                                  struct bch_extent_ptr *ptr,
@@ -884,9 +925,9 @@ static void ec_stripe_create(struct ec_stripe_new *s)
        }
 
        ret = s->have_existing_stripe
-               ? bch2_btree_insert(c, BTREE_ID_EC, &s->new_stripe.key.k_i,
-                                   &s->res, NULL, BTREE_INSERT_NOFAIL)
-               : ec_stripe_bkey_insert(c, s, &s->new_stripe.key);
+               ? bch2_trans_do(c, &s->res, NULL, BTREE_INSERT_NOFAIL,
+                               ec_stripe_bkey_update(&trans, &s->new_stripe.key))
+               : ec_stripe_bkey_insert(c, &s->new_stripe.key, &s->res);
        if (ret) {
                bch_err(c, "error creating stripe: error creating stripe key");
                goto err_put_writes;
@@ -902,11 +943,7 @@ static void ec_stripe_create(struct ec_stripe_new *s)
 
        spin_lock(&c->ec_stripes_heap_lock);
        m = genradix_ptr(&c->stripes[0], s->new_stripe.key.k.p.offset);
-#if 0
-       pr_info("created a %s stripe %llu",
-               s->have_existing_stripe ? "existing" : "new",
-               s->stripe.key.k.p.offset);
-#endif
+
        BUG_ON(m->on_heap);
        bch2_stripes_heap_insert(c, m, s->new_stripe.key.k.p.offset);
        spin_unlock(&c->ec_stripes_heap_lock);