bcachefs: Erasure coding now uses bch2_bucket_alloc_trans

This code predates plumbing btree_trans through the bucket allocation
path: switching to it fixes a deadlock due to using multiple btree_trans
at the same time, which we never want to do.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/alloc_foreground.c

@@ -713,7 +713,7 @@ static void add_new_bucket(struct bch_fs *c,
 	ob_push(c, ptrs, ob);
 }
 
-static int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
+int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 		      struct open_buckets *ptrs,
 		      struct dev_stripe_state *stripe,
 		      struct bch_devs_mask *devs_may_alloc,
@@ -779,24 +779,6 @@ static int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 	return ret;
 }
 
-int bch2_bucket_alloc_set(struct bch_fs *c,
-		      struct open_buckets *ptrs,
-		      struct dev_stripe_state *stripe,
-		      struct bch_devs_mask *devs_may_alloc,
-		      unsigned nr_replicas,
-		      unsigned *nr_effective,
-		      bool *have_cache,
-		      enum alloc_reserve reserve,
-		      unsigned flags,
-		      struct closure *cl)
-{
-	return bch2_trans_do(c, NULL, NULL, 0,
-		      bch2_bucket_alloc_set_trans(&trans, ptrs, stripe,
-					      devs_may_alloc, nr_replicas,
-					      nr_effective, have_cache, reserve,
-					      flags, cl));
-}
-
 /* Allocate from stripes: */
 
 /*
@@ -805,7 +787,7 @@ int bch2_bucket_alloc_set(struct bch_fs *c,
  * it's to a device we don't want:
  */
 
-static int bucket_alloc_from_stripe(struct bch_fs *c,
+static int bucket_alloc_from_stripe(struct btree_trans *trans,
 			 struct open_buckets *ptrs,
 			 struct write_point *wp,
 			 struct bch_devs_mask *devs_may_alloc,
@@ -817,6 +799,7 @@ static int bucket_alloc_from_stripe(struct bch_fs *c,
 			 unsigned flags,
 			 struct closure *cl)
 {
+	struct bch_fs *c = trans->c;
 	struct dev_alloc_list devs_sorted;
 	struct ec_stripe_head *h;
 	struct open_bucket *ob;
@@ -832,11 +815,11 @@ static int bucket_alloc_from_stripe(struct bch_fs *c,
 	if (ec_open_bucket(c, ptrs))
 		return 0;
 
-	h = bch2_ec_stripe_head_get(c, target, 0, nr_replicas - 1,
+	h = bch2_ec_stripe_head_get(trans, target, 0, nr_replicas - 1,
 				    wp == &c->copygc_write_point,
 				    cl);
 	if (IS_ERR(h))
-		return -PTR_ERR(h);
+		return PTR_ERR(h);
 	if (!h)
 		return 0;
 
@@ -942,7 +925,7 @@ static int open_bucket_add_buckets(struct btree_trans *trans,
 		}
 
 		if (!ec_open_bucket(c, ptrs)) {
-			ret = bucket_alloc_from_stripe(c, ptrs, wp, &devs,
+			ret = bucket_alloc_from_stripe(trans, ptrs, wp, &devs,
 						 target, erasure_code,
 						 nr_replicas, nr_effective,
 						 have_cache, flags, _cl);

fs/bcachefs/alloc_foreground.h

@@ -150,7 +150,7 @@ static inline bool bch2_bucket_is_open_safe(struct bch_fs *c, unsigned dev, u64
 	return ret;
 }
 
-int bch2_bucket_alloc_set(struct bch_fs *, struct open_buckets *,
+int bch2_bucket_alloc_set_trans(struct btree_trans *, struct open_buckets *,
 		      struct dev_stripe_state *, struct bch_devs_mask *,
 		      unsigned, unsigned *, bool *, enum alloc_reserve,
 		      unsigned, struct closure *);

fs/bcachefs/ec.c

@@ -1294,9 +1294,10 @@ struct ec_stripe_head *__bch2_ec_stripe_head_get(struct bch_fs *c,
 	return h;
 }
 
-static int new_stripe_alloc_buckets(struct bch_fs *c, struct ec_stripe_head *h,
+static int new_stripe_alloc_buckets(struct btree_trans *trans, struct ec_stripe_head *h,
 				    struct closure *cl)
 {
+	struct bch_fs *c = trans->c;
 	struct bch_devs_mask devs = h->devs;
 	struct open_bucket *ob;
 	struct open_buckets buckets;
@@ -1319,7 +1320,7 @@ static int new_stripe_alloc_buckets(struct bch_fs *c, struct ec_stripe_head *h,
 
 	buckets.nr = 0;
 	if (nr_have_parity < h->s->nr_parity) {
-		ret = bch2_bucket_alloc_set(c, &buckets,
+		ret = bch2_bucket_alloc_set_trans(trans, &buckets,
 					    &h->parity_stripe,
 					    &devs,
 					    h->s->nr_parity,
@@ -1348,7 +1349,7 @@ static int new_stripe_alloc_buckets(struct bch_fs *c, struct ec_stripe_head *h,
 
 	buckets.nr = 0;
 	if (nr_have_data < h->s->nr_data) {
-		ret = bch2_bucket_alloc_set(c, &buckets,
+		ret = bch2_bucket_alloc_set_trans(trans, &buckets,
 					    &h->block_stripe,
 					    &devs,
 					    h->s->nr_data,
@@ -1464,13 +1465,14 @@ static int __bch2_ec_stripe_head_reserve(struct bch_fs *c,
 					 h->s->nr_parity, 0);
 }
 
-struct ec_stripe_head *bch2_ec_stripe_head_get(struct bch_fs *c,
+struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *trans,
 					       unsigned target,
 					       unsigned algo,
 					       unsigned redundancy,
 					       bool copygc,
 					       struct closure *cl)
 {
+	struct bch_fs *c = trans->c;
 	struct ec_stripe_head *h;
 	int ret;
 	bool needs_stripe_new;
@@ -1509,7 +1511,7 @@ struct ec_stripe_head *bch2_ec_stripe_head_get(struct bch_fs *c,
 	}
 
 	if (!h->s->allocated) {
-		ret = new_stripe_alloc_buckets(c, h, cl);
+		ret = new_stripe_alloc_buckets(trans, h, cl);
 		if (ret)
 			goto err;
 
@@ -1517,7 +1519,6 @@ struct ec_stripe_head *bch2_ec_stripe_head_get(struct bch_fs *c,
 	}
 
 	return h;
-
 err:
 	bch2_ec_stripe_head_put(c, h);
 	return ERR_PTR(ret);

fs/bcachefs/ec.h

@@ -200,7 +200,7 @@ void bch2_ec_bucket_cancel(struct bch_fs *, struct open_bucket *);
 int bch2_ec_stripe_new_alloc(struct bch_fs *, struct ec_stripe_head *);
 
 void bch2_ec_stripe_head_put(struct bch_fs *, struct ec_stripe_head *);
-struct ec_stripe_head *bch2_ec_stripe_head_get(struct bch_fs *,
+struct ec_stripe_head *bch2_ec_stripe_head_get(struct btree_trans *,
 			unsigned, unsigned, unsigned, bool, struct closure *);
 
 void bch2_stripes_heap_update(struct bch_fs *, struct stripe *, size_t);