1 files changed, 826 insertions, 306 deletions

diff --git a/fs/bcachefs/alloc_foreground.c b/fs/bcachefs/alloc_foreground.c
index 0a634125dc90..350635f3b118 100644
--- a/fs/bcachefs/alloc_foreground.c
+++ b/fs/bcachefs/alloc_foreground.c
@@ -14,19 +14,34 @@
 #include "bcachefs.h"
 #include "alloc_background.h"
 #include "alloc_foreground.h"
+#include "backpointers.h"
+#include "btree_iter.h"
+#include "btree_update.h"
 #include "btree_gc.h"
 #include "buckets.h"
+#include "buckets_waiting_for_journal.h"
 #include "clock.h"
 #include "debug.h"
 #include "disk_groups.h"
 #include "ec.h"
+#include "error.h"
 #include "io.h"
+#include "journal.h"
+#include "movinggc.h"
+#include "nocow_locking.h"
 
 #include <linux/math64.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
 #include <trace/events/bcachefs.h>
 
+const char * const bch2_alloc_reserves[] = {
+#define x(t) #t,
+	BCH_ALLOC_RESERVES()
+#undef x
+	NULL
+};
+
 /*
  * Open buckets represent a bucket that's currently being allocated from.  They
  * serve two purposes:
@@ -43,6 +58,17 @@
  * reference _after_ doing the index update that makes its allocation reachable.
  */
 
+void bch2_reset_alloc_cursors(struct bch_fs *c)
+{
+	struct bch_dev *ca;
+	unsigned i;
+
+	rcu_read_lock();
+	for_each_member_device_rcu(ca, c, i, NULL)
+		ca->alloc_cursor = 0;
+	rcu_read_unlock();
+}
+
 static void bch2_open_bucket_hash_add(struct bch_fs *c, struct open_bucket *ob)
 {
 	open_bucket_idx_t idx = ob - c->open_buckets;
@@ -71,14 +97,13 @@ void __bch2_open_bucket_put(struct bch_fs *c, struct open_bucket *ob)
 	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
 
 	if (ob->ec) {
-		bch2_ec_bucket_written(c, ob);
+		ec_stripe_new_put(c, ob->ec, STRIPE_REF_io);
 		return;
 	}
 
 	percpu_down_read(&c->mark_lock);
 	spin_lock(&ob->lock);
 
-	bch2_mark_alloc_bucket(c, ca, ob->bucket, false);
 	ob->valid = false;
 	ob->data_type = 0;
 
@@ -129,42 +154,17 @@ static void open_bucket_free_unused(struct bch_fs *c,
 				    struct write_point *wp,
 				    struct open_bucket *ob)
 {
-	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
-	bool may_realloc = wp->data_type == BCH_DATA_user;
-
-	BUG_ON(ca->open_buckets_partial_nr >
-	       ARRAY_SIZE(ca->open_buckets_partial));
-
-	if (ca->open_buckets_partial_nr <
-	    ARRAY_SIZE(ca->open_buckets_partial) &&
-	    may_realloc) {
-		spin_lock(&c->freelist_lock);
-		ob->on_partial_list = true;
-		ca->open_buckets_partial[ca->open_buckets_partial_nr++] =
-			ob - c->open_buckets;
-		spin_unlock(&c->freelist_lock);
+	BUG_ON(c->open_buckets_partial_nr >=
+	       ARRAY_SIZE(c->open_buckets_partial));
 
-		closure_wake_up(&c->open_buckets_wait);
-		closure_wake_up(&c->freelist_wait);
-	} else {
-		bch2_open_bucket_put(c, ob);
-	}
-}
-
-static void verify_not_stale(struct bch_fs *c, const struct open_buckets *obs)
-{
-#ifdef CONFIG_BCACHEFS_DEBUG
-	struct open_bucket *ob;
-	unsigned i;
-
-	rcu_read_lock();
-	open_bucket_for_each(c, obs, ob, i) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	spin_lock(&c->freelist_lock);
+	ob->on_partial_list = true;
+	c->open_buckets_partial[c->open_buckets_partial_nr++] =
+		ob - c->open_buckets;
+	spin_unlock(&c->freelist_lock);
 
-		BUG_ON(*bucket_gen(ca, ob->bucket) != ob->gen);
-	}
-	rcu_read_unlock();
-#endif
+	closure_wake_up(&c->open_buckets_wait);
+	closure_wake_up(&c->freelist_wait);
 }
 
 /* _only_ for allocating the journal on a new device: */
@@ -184,49 +184,48 @@ long bch2_bucket_alloc_new_fs(struct bch_dev *ca)
 static inline unsigned open_buckets_reserved(enum alloc_reserve reserve)
 {
 	switch (reserve) {
-	case RESERVE_BTREE:
-	case RESERVE_BTREE_MOVINGGC:
+	case RESERVE_btree:
+	case RESERVE_btree_movinggc:
 		return 0;
-	case RESERVE_MOVINGGC:
+	case RESERVE_movinggc:
 		return OPEN_BUCKETS_COUNT / 4;
 	default:
 		return OPEN_BUCKETS_COUNT / 2;
 	}
 }
 
-/**
- * bch_bucket_alloc - allocate a single bucket from a specific device
- *
- * Returns index of bucket on success, 0 on failure
- * */
-struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
-				      enum alloc_reserve reserve,
-				      bool may_alloc_partial,
-				      struct closure *cl)
+static struct open_bucket *__try_alloc_bucket(struct bch_fs *c, struct bch_dev *ca,
+					      u64 bucket,
+					      enum alloc_reserve reserve,
+					      const struct bch_alloc_v4 *a,
+					      struct bucket_alloc_state *s,
+					      struct closure *cl)
 {
 	struct open_bucket *ob;
-	long b = 0;
 
-	spin_lock(&c->freelist_lock);
+	if (unlikely(ca->buckets_nouse && test_bit(bucket, ca->buckets_nouse))) {
+		s->skipped_nouse++;
+		return NULL;
+	}
 
-	if (may_alloc_partial) {
-		int i;
+	if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
+		s->skipped_open++;
+		return NULL;
+	}
 
-		for (i = ca->open_buckets_partial_nr - 1; i >= 0; --i) {
-			ob = c->open_buckets + ca->open_buckets_partial[i];
+	if (bch2_bucket_needs_journal_commit(&c->buckets_waiting_for_journal,
+			c->journal.flushed_seq_ondisk, ca->dev_idx, bucket)) {
+		s->skipped_need_journal_commit++;
+		return NULL;
+	}
 
-			if (reserve <= ob->alloc_reserve) {
-				array_remove_item(ca->open_buckets_partial,
-						  ca->open_buckets_partial_nr,
-						  i);
-				ob->on_partial_list = false;
-				ob->alloc_reserve = reserve;
-				spin_unlock(&c->freelist_lock);
-				return ob;
-			}
-		}
+	if (bch2_bucket_nocow_is_locked(&c->nocow_locks, POS(ca->dev_idx, bucket))) {
+		s->skipped_nocow++;
+		return NULL;
 	}
 
+	spin_lock(&c->freelist_lock);
+
 	if (unlikely(c->open_buckets_nr_free <= open_buckets_reserved(reserve))) {
 		if (cl)
 			closure_wait(&c->open_buckets_wait, cl);
@@ -235,46 +234,25 @@ struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
 			c->blocked_allocate_open_bucket = local_clock();
 
 		spin_unlock(&c->freelist_lock);
-		trace_open_bucket_alloc_fail(ca, reserve);
-		return ERR_PTR(-OPEN_BUCKETS_EMPTY);
+		return ERR_PTR(-BCH_ERR_open_buckets_empty);
 	}
 
-	if (likely(fifo_pop(&ca->free[RESERVE_NONE], b)))
-		goto out;
-
-	switch (reserve) {
-	case RESERVE_BTREE_MOVINGGC:
-	case RESERVE_MOVINGGC:
-		if (fifo_pop(&ca->free[RESERVE_MOVINGGC], b))
-			goto out;
-		break;
-	default:
-		break;
+	/* Recheck under lock: */
+	if (bch2_bucket_is_open(c, ca->dev_idx, bucket)) {
+		spin_unlock(&c->freelist_lock);
+		s->skipped_open++;
+		return NULL;
 	}
 
-	if (cl)
-		closure_wait(&c->freelist_wait, cl);
-
-	if (!c->blocked_allocate)
-		c->blocked_allocate = local_clock();
-
-	spin_unlock(&c->freelist_lock);
-
-	trace_bucket_alloc_fail(ca, reserve);
-	return ERR_PTR(-FREELIST_EMPTY);
-out:
-	verify_not_on_freelist(c, ca, b);
-
 	ob = bch2_open_bucket_alloc(c);
 
 	spin_lock(&ob->lock);
 
 	ob->valid	= true;
 	ob->sectors_free = ca->mi.bucket_size;
-	ob->alloc_reserve = reserve;
 	ob->dev		= ca->dev_idx;
-	ob->gen		= *bucket_gen(ca, b);
-	ob->bucket	= b;
+	ob->gen		= a->gen;
+	ob->bucket	= bucket;
 	spin_unlock(&ob->lock);
 
 	ca->nr_open_buckets++;
@@ -295,10 +273,322 @@ out:
 	}
 
 	spin_unlock(&c->freelist_lock);
+	return ob;
+}
+
+static struct open_bucket *try_alloc_bucket(struct btree_trans *trans, struct bch_dev *ca,
+					    enum alloc_reserve reserve, u64 free_entry,
+					    struct bucket_alloc_state *s,
+					    struct bkey_s_c freespace_k,
+					    struct closure *cl)
+{
+	struct bch_fs *c = trans->c;
+	struct btree_iter iter = { NULL };
+	struct bkey_s_c k;
+	struct open_bucket *ob;
+	struct bch_alloc_v4 a_convert;
+	const struct bch_alloc_v4 *a;
+	u64 b = free_entry & ~(~0ULL << 56);
+	unsigned genbits = free_entry >> 56;
+	struct printbuf buf = PRINTBUF;
+	int ret;
+
+	if (b < ca->mi.first_bucket || b >= ca->mi.nbuckets) {
+		prt_printf(&buf, "freespace btree has bucket outside allowed range %u-%llu\n"
+		       "  freespace key ",
+			ca->mi.first_bucket, ca->mi.nbuckets);
+		bch2_bkey_val_to_text(&buf, c, freespace_k);
+		bch2_trans_inconsistent(trans, "%s", buf.buf);
+		ob = ERR_PTR(-EIO);
+		goto err;
+	}
+
+	bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc, POS(ca->dev_idx, b), BTREE_ITER_CACHED);
+	k = bch2_btree_iter_peek_slot(&iter);
+	ret = bkey_err(k);
+	if (ret) {
+		ob = ERR_PTR(ret);
+		goto err;
+	}
+
+	a = bch2_alloc_to_v4(k, &a_convert);
+
+	if (a->data_type != BCH_DATA_free) {
+		if (!test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
+			ob = NULL;
+			goto err;
+		}
+
+		prt_printf(&buf, "non free bucket in freespace btree\n"
+		       "  freespace key ");
+		bch2_bkey_val_to_text(&buf, c, freespace_k);
+		prt_printf(&buf, "\n  ");
+		bch2_bkey_val_to_text(&buf, c, k);
+		bch2_trans_inconsistent(trans, "%s", buf.buf);
+		ob = ERR_PTR(-EIO);
+		goto err;
+	}
+
+	if (genbits != (alloc_freespace_genbits(*a) >> 56) &&
+	    test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
+		prt_printf(&buf, "bucket in freespace btree with wrong genbits (got %u should be %llu)\n"
+		       "  freespace key ",
+		       genbits, alloc_freespace_genbits(*a) >> 56);
+		bch2_bkey_val_to_text(&buf, c, freespace_k);
+		prt_printf(&buf, "\n  ");
+		bch2_bkey_val_to_text(&buf, c, k);
+		bch2_trans_inconsistent(trans, "%s", buf.buf);
+		ob = ERR_PTR(-EIO);
+		goto err;
+
+	}
+
+	if (!test_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags)) {
+		struct bch_backpointer bp;
+		struct bpos bp_pos = POS_MIN;
+
+		ret = bch2_get_next_backpointer(trans, POS(ca->dev_idx, b), -1,
+						&bp_pos, &bp,
+						BTREE_ITER_NOPRESERVE);
+		if (ret) {
+			ob = ERR_PTR(ret);
+			goto err;
+		}
+
+		if (!bkey_eq(bp_pos, POS_MAX)) {
+			/*
+			 * Bucket may have data in it - we don't call
+			 * bc2h_trans_inconnsistent() because fsck hasn't
+			 * finished yet
+			 */
+			ob = NULL;
+			goto err;
+		}
+	}
+
+	ob = __try_alloc_bucket(c, ca, b, reserve, a, s, cl);
+	if (!ob)
+		iter.path->preserve = false;
+err:
+	set_btree_iter_dontneed(&iter);
+	bch2_trans_iter_exit(trans, &iter);
+	printbuf_exit(&buf);
+	return ob;
+}
+
+/*
+ * This path is for before the freespace btree is initialized:
+ *
+ * If ca->new_fs_bucket_idx is nonzero, we haven't yet marked superblock &
+ * journal buckets - journal buckets will be < ca->new_fs_bucket_idx
+ */
+static noinline struct open_bucket *
+bch2_bucket_alloc_early(struct btree_trans *trans,
+			struct bch_dev *ca,
+			enum alloc_reserve reserve,
+			struct bucket_alloc_state *s,
+			struct closure *cl)
+{
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	struct open_bucket *ob = NULL;
+	u64 alloc_start = max_t(u64, ca->mi.first_bucket, ca->new_fs_bucket_idx);
+	u64 alloc_cursor = max(alloc_start, READ_ONCE(ca->alloc_cursor));
+	int ret;
+again:
+	for_each_btree_key_norestart(trans, iter, BTREE_ID_alloc, POS(ca->dev_idx, alloc_cursor),
+			   BTREE_ITER_SLOTS, k, ret) {
+		struct bch_alloc_v4 a_convert;
+		const struct bch_alloc_v4 *a;
 
-	bch2_wake_allocator(ca);
+		if (bkey_ge(k.k->p, POS(ca->dev_idx, ca->mi.nbuckets)))
+			break;
+
+		if (ca->new_fs_bucket_idx &&
+		    is_superblock_bucket(ca, k.k->p.offset))
+			continue;
+
+		a = bch2_alloc_to_v4(k, &a_convert);
+
+		if (a->data_type != BCH_DATA_free)
+			continue;
+
+		s->buckets_seen++;
+
+		ob = __try_alloc_bucket(trans->c, ca, k.k->p.offset, reserve, a, s, cl);
+		if (ob)
+			break;
+	}
+	bch2_trans_iter_exit(trans, &iter);
+
+	ca->alloc_cursor = alloc_cursor;
+
+	if (!ob && ret)
+		ob = ERR_PTR(ret);
+
+	if (!ob && alloc_cursor > alloc_start) {
+		alloc_cursor = alloc_start;
+		goto again;
+	}
+
+	return ob;
+}
+
+static struct open_bucket *bch2_bucket_alloc_freelist(struct btree_trans *trans,
+						   struct bch_dev *ca,
+						   enum alloc_reserve reserve,
+						   struct bucket_alloc_state *s,
+						   struct closure *cl)
+{
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	struct open_bucket *ob = NULL;
+	u64 alloc_start = max_t(u64, ca->mi.first_bucket, READ_ONCE(ca->alloc_cursor));
+	u64 alloc_cursor = alloc_start;
+	int ret;
+
+	BUG_ON(ca->new_fs_bucket_idx);
+again:
+	for_each_btree_key_norestart(trans, iter, BTREE_ID_freespace,
+				     POS(ca->dev_idx, alloc_cursor), 0, k, ret) {
+		if (k.k->p.inode != ca->dev_idx)
+			break;
+
+		for (alloc_cursor = max(alloc_cursor, bkey_start_offset(k.k));
+		     alloc_cursor < k.k->p.offset;
+		     alloc_cursor++) {
+			ret = btree_trans_too_many_iters(trans);
+			if (ret) {
+				ob = ERR_PTR(ret);
+				break;
+			}
+
+			s->buckets_seen++;
+
+			ob = try_alloc_bucket(trans, ca, reserve,
+					      alloc_cursor, s, k, cl);
+			if (ob) {
+				iter.path->preserve = false;
+				break;
+			}
+		}
+
+		if (ob || ret)
+			break;
+	}
+	bch2_trans_iter_exit(trans, &iter);
+
+	ca->alloc_cursor = alloc_cursor;
+
+	if (!ob && ret)
+		ob = ERR_PTR(ret);
+
+	if (!ob && alloc_start > ca->mi.first_bucket) {
+		alloc_cursor = alloc_start = ca->mi.first_bucket;
+		goto again;
+	}
 
-	trace_bucket_alloc(ca, reserve);
+	return ob;
+}
+
+/**
+ * bch_bucket_alloc - allocate a single bucket from a specific device
+ *
+ * Returns index of bucket on success, 0 on failure
+ */
+static struct open_bucket *bch2_bucket_alloc_trans(struct btree_trans *trans,
+				      struct bch_dev *ca,
+				      enum alloc_reserve reserve,
+				      struct closure *cl,
+				      struct bch_dev_usage *usage)
+{
+	struct bch_fs *c = trans->c;
+	struct open_bucket *ob = NULL;
+	bool freespace = READ_ONCE(ca->mi.freespace_initialized);
+	u64 avail;
+	struct bucket_alloc_state s = { 0 };
+	bool waiting = false;
+again:
+	bch2_dev_usage_read_fast(ca, usage);
+	avail = dev_buckets_free(ca, *usage, reserve);
+
+	if (usage->d[BCH_DATA_need_discard].buckets > avail)
+		bch2_do_discards(c);
+
+	if (usage->d[BCH_DATA_need_gc_gens].buckets > avail)
+		bch2_do_gc_gens(c);
+
+	if (should_invalidate_buckets(ca, *usage))
+		bch2_do_invalidates(c);
+
+	if (!avail) {
+		if (cl && !waiting) {
+			closure_wait(&c->freelist_wait, cl);
+			waiting = true;
+			goto again;
+		}
+
+		if (!c->blocked_allocate)
+			c->blocked_allocate = local_clock();
+
+		ob = ERR_PTR(-BCH_ERR_freelist_empty);
+		goto err;
+	}
+
+	if (waiting)
+		closure_wake_up(&c->freelist_wait);
+alloc:
+	ob = likely(freespace)
+		? bch2_bucket_alloc_freelist(trans, ca, reserve, &s, cl)
+		: bch2_bucket_alloc_early(trans, ca, reserve, &s, cl);
+
+	if (s.skipped_need_journal_commit * 2 > avail)
+		bch2_journal_flush_async(&c->journal, NULL);
+
+	if (!ob && freespace && !test_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags)) {
+		freespace = false;
+		goto alloc;
+	}
+err:
+	if (!ob)
+		ob = ERR_PTR(-BCH_ERR_no_buckets_found);
+
+	if (!IS_ERR(ob))
+		trace_and_count(c, bucket_alloc, ca,
+				bch2_alloc_reserves[reserve],
+				ob->bucket,
+				usage->d[BCH_DATA_free].buckets,
+				avail,
+				bch2_copygc_wait_amount(c),
+				c->copygc_wait - atomic64_read(&c->io_clock[WRITE].now),
+				&s,
+				cl == NULL,
+				"");
+	else if (!bch2_err_matches(PTR_ERR(ob), BCH_ERR_transaction_restart))
+		trace_and_count(c, bucket_alloc_fail, ca,
+				bch2_alloc_reserves[reserve],
+				0,
+				usage->d[BCH_DATA_free].buckets,
+				avail,
+				bch2_copygc_wait_amount(c),
+				c->copygc_wait - atomic64_read(&c->io_clock[WRITE].now),
+				&s,
+				cl == NULL,
+				bch2_err_str(PTR_ERR(ob)));
+
+	return ob;
+}
+
+struct open_bucket *bch2_bucket_alloc(struct bch_fs *c, struct bch_dev *ca,
+				      enum alloc_reserve reserve,
+				      struct closure *cl)
+{
+	struct bch_dev_usage usage;
+	struct open_bucket *ob;
+
+	bch2_trans_do(c, NULL, NULL, 0,
+		      PTR_ERR_OR_ZERO(ob = bch2_bucket_alloc_trans(&trans, ca, reserve,
+							cl, &usage)));
 	return ob;
 }
 
@@ -325,11 +615,12 @@ struct dev_alloc_list bch2_dev_alloc_list(struct bch_fs *c,
 	return ret;
 }
 
-void bch2_dev_stripe_increment(struct bch_dev *ca,
-			       struct dev_stripe_state *stripe)
+static inline void bch2_dev_stripe_increment_inlined(struct bch_dev *ca,
+			       struct dev_stripe_state *stripe,
+			       struct bch_dev_usage *usage)
 {
 	u64 *v = stripe->next_alloc + ca->dev_idx;
-	u64 free_space = dev_buckets_available(ca);
+	u64 free_space = dev_buckets_available(ca, RESERVE_none);
 	u64 free_space_inv = free_space
 		? div64_u64(1ULL << 48, free_space)
 		: 1ULL << 48;
@@ -345,12 +636,19 @@ void bch2_dev_stripe_increment(struct bch_dev *ca,
 		*v = *v < scale ? 0 : *v - scale;
 }
 
-#define BUCKET_MAY_ALLOC_PARTIAL	(1 << 0)
-#define BUCKET_ALLOC_USE_DURABILITY	(1 << 1)
+void bch2_dev_stripe_increment(struct bch_dev *ca,
+			       struct dev_stripe_state *stripe)
+{
+	struct bch_dev_usage usage;
 
-static void add_new_bucket(struct bch_fs *c,
+	bch2_dev_usage_read_fast(ca, &usage);
+	bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
+}
+
+static int add_new_bucket(struct bch_fs *c,
 			   struct open_buckets *ptrs,
 			   struct bch_devs_mask *devs_may_alloc,
+			   unsigned nr_replicas,
 			   unsigned *nr_effective,
 			   bool *have_cache,
 			   unsigned flags,
@@ -359,60 +657,85 @@ static void add_new_bucket(struct bch_fs *c,
 	unsigned durability =
 		bch_dev_bkey_exists(c, ob->dev)->mi.durability;
 
+	BUG_ON(*nr_effective >= nr_replicas);
+	BUG_ON(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS);
+
 	__clear_bit(ob->dev, devs_may_alloc->d);
-	*nr_effective	+= (flags & BUCKET_ALLOC_USE_DURABILITY)
+	*nr_effective	+= (flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)
 		? durability : 1;
 	*have_cache	|= !durability;
 
 	ob_push(c, ptrs, ob);
+
+	if (*nr_effective >= nr_replicas)
+		return 1;
+	if (ob->ec)
+		return 1;
+	return 0;
 }
 
-int bch2_bucket_alloc_set(struct bch_fs *c,
+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,
 		      unsigned nr_replicas,
 		      unsigned *nr_effective,
 		      bool *have_cache,
-		      enum alloc_reserve reserve,
 		      unsigned flags,
+		      enum bch_data_type data_type,
+		      enum alloc_reserve reserve,
 		      struct closure *cl)
 {
+	struct bch_fs *c = trans->c;
 	struct dev_alloc_list devs_sorted =
 		bch2_dev_alloc_list(c, stripe, devs_may_alloc);
+	unsigned dev;
 	struct bch_dev *ca;
-	int ret = -INSUFFICIENT_DEVICES;
+	int ret = -BCH_ERR_insufficient_devices;
 	unsigned i;
 
 	BUG_ON(*nr_effective >= nr_replicas);
 
 	for (i = 0; i < devs_sorted.nr; i++) {
+		struct bch_dev_usage usage;
 		struct open_bucket *ob;
 
-		ca = rcu_dereference(c->devs[devs_sorted.devs[i]]);
+		dev = devs_sorted.devs[i];
+
+		rcu_read_lock();
+		ca = rcu_dereference(c->devs[dev]);
+		if (ca)
+			percpu_ref_get(&ca->ref);
+		rcu_read_unlock();
+
 		if (!ca)
 			continue;
 
-		if (!ca->mi.durability && *have_cache)
+		if (!ca->mi.durability && *have_cache) {
+			percpu_ref_put(&ca->ref);
 			continue;
+		}
+
+		ob = bch2_bucket_alloc_trans(trans, ca, reserve, cl, &usage);
+		if (!IS_ERR(ob))
+			bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
+		percpu_ref_put(&ca->ref);
 
-		ob = bch2_bucket_alloc(c, ca, reserve,
-				flags & BUCKET_MAY_ALLOC_PARTIAL, cl);
 		if (IS_ERR(ob)) {
 			ret = PTR_ERR(ob);
-
-			if (cl)
-				return ret;
+			if (bch2_err_matches(ret, BCH_ERR_transaction_restart) || cl)
+				break;
 			continue;
 		}
 
-		add_new_bucket(c, ptrs, devs_may_alloc,
-			       nr_effective, have_cache, flags, ob);
+		ob->data_type = data_type;
 
-		bch2_dev_stripe_increment(ca, stripe);
-
-		if (*nr_effective >= nr_replicas)
-			return 0;
+		if (add_new_bucket(c, ptrs, devs_may_alloc,
+				   nr_replicas, nr_effective,
+				   have_cache, flags, ob)) {
+			ret = 0;
+			break;
+		}
 	}
 
 	return ret;
@@ -426,26 +749,25 @@ 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,
 			 u16 target,
-			 unsigned erasure_code,
 			 unsigned nr_replicas,
 			 unsigned *nr_effective,
 			 bool *have_cache,
+			 enum alloc_reserve reserve,
 			 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;
 	struct bch_dev *ca;
 	unsigned i, ec_idx;
-
-	if (!erasure_code)
-		return 0;
+	int ret = 0;
 
 	if (nr_replicas < 2)
 		return 0;
@@ -453,11 +775,9 @@ 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,
-				    wp == &c->copygc_write_point,
-				    cl);
+	h = bch2_ec_stripe_head_get(trans, target, 0, nr_replicas - 1, reserve, cl);
 	if (IS_ERR(h))
-		return -PTR_ERR(h);
+		return PTR_ERR(h);
 	if (!h)
 		return 0;
 
@@ -479,55 +799,126 @@ got_bucket:
 
 	ob->ec_idx	= ec_idx;
 	ob->ec		= h->s;
+	ec_stripe_new_get(h->s, STRIPE_REF_io);
 
-	add_new_bucket(c, ptrs, devs_may_alloc,
-		       nr_effective, have_cache, flags, ob);
-	atomic_inc(&h->s->pin);
+	ret = add_new_bucket(c, ptrs, devs_may_alloc,
+			     nr_replicas, nr_effective,
+			     have_cache, flags, ob);
 out_put_head:
 	bch2_ec_stripe_head_put(c, h);
-	return 0;
+	return ret;
 }
 
 /* Sector allocator */
 
-static void get_buckets_from_writepoint(struct bch_fs *c,
-					struct open_buckets *ptrs,
-					struct write_point *wp,
-					struct bch_devs_mask *devs_may_alloc,
-					unsigned nr_replicas,
-					unsigned *nr_effective,
-					bool *have_cache,
-					unsigned flags,
-					bool need_ec)
+static bool want_bucket(struct bch_fs *c,
+			struct write_point *wp,
+			struct bch_devs_mask *devs_may_alloc,
+			bool *have_cache, bool ec,
+			struct open_bucket *ob)
+{
+	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+
+	if (!test_bit(ob->dev, devs_may_alloc->d))
+		return false;
+
+	if (ob->data_type != wp->data_type)
+		return false;
+
+	if (!ca->mi.durability &&
+	    (wp->data_type == BCH_DATA_btree || ec || *have_cache))
+		return false;
+
+	if (ec != (ob->ec != NULL))
+		return false;
+
+	return true;
+}
+
+static int bucket_alloc_set_writepoint(struct bch_fs *c,
+				       struct open_buckets *ptrs,
+				       struct write_point *wp,
+				       struct bch_devs_mask *devs_may_alloc,
+				       unsigned nr_replicas,
+				       unsigned *nr_effective,
+				       bool *have_cache,
+				       bool ec, unsigned flags)
 {
 	struct open_buckets ptrs_skip = { .nr = 0 };
 	struct open_bucket *ob;
 	unsigned i;
+	int ret = 0;
 
 	open_bucket_for_each(c, &wp->ptrs, ob, i) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
-
-		if (*nr_effective < nr_replicas &&
-		    test_bit(ob->dev, devs_may_alloc->d) &&
-		    (ca->mi.durability ||
-		     (wp->data_type == BCH_DATA_user && !*have_cache)) &&
-		    (ob->ec || !need_ec)) {
-			add_new_bucket(c, ptrs, devs_may_alloc,
-				       nr_effective, have_cache,
-				       flags, ob);
-		} else {
+		if (!ret && want_bucket(c, wp, devs_may_alloc,
+					have_cache, ec, ob))
+			ret = add_new_bucket(c, ptrs, devs_may_alloc,
+				       nr_replicas, nr_effective,
+				       have_cache, flags, ob);
+		else
 			ob_push(c, &ptrs_skip, ob);
-		}
 	}
 	wp->ptrs = ptrs_skip;
+
+	return ret;
+}
+
+static int bucket_alloc_set_partial(struct bch_fs *c,
+				    struct open_buckets *ptrs,
+				    struct write_point *wp,
+				    struct bch_devs_mask *devs_may_alloc,
+				    unsigned nr_replicas,
+				    unsigned *nr_effective,
+				    bool *have_cache, bool ec,
+				    enum alloc_reserve reserve,
+				    unsigned flags)
+{
+	int i, ret = 0;
+
+	if (!c->open_buckets_partial_nr)
+		return 0;
+
+	spin_lock(&c->freelist_lock);
+
+	if (!c->open_buckets_partial_nr)
+		goto unlock;
+
+	for (i = c->open_buckets_partial_nr - 1; i >= 0; --i) {
+		struct open_bucket *ob = c->open_buckets + c->open_buckets_partial[i];
+
+		if (want_bucket(c, wp, devs_may_alloc, have_cache, ec, ob)) {
+			struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+			struct bch_dev_usage usage;
+			u64 avail;
+
+			bch2_dev_usage_read_fast(ca, &usage);
+			avail = dev_buckets_free(ca, usage, reserve);
+			if (!avail)
+				continue;
+
+			array_remove_item(c->open_buckets_partial,
+					  c->open_buckets_partial_nr,
+					  i);
+			ob->on_partial_list = false;
+
+			ret = add_new_bucket(c, ptrs, devs_may_alloc,
+					     nr_replicas, nr_effective,
+					     have_cache, flags, ob);
+			if (ret)
+				break;
+		}
+	}
+unlock:
+	spin_unlock(&c->freelist_lock);
+	return ret;
 }
 
-static int open_bucket_add_buckets(struct bch_fs *c,
+static int __open_bucket_add_buckets(struct btree_trans *trans,
 			struct open_buckets *ptrs,
 			struct write_point *wp,
 			struct bch_devs_list *devs_have,
 			u16 target,
-			unsigned erasure_code,
+			bool erasure_code,
 			unsigned nr_replicas,
 			unsigned *nr_effective,
 			bool *have_cache,
@@ -535,11 +926,12 @@ static int open_bucket_add_buckets(struct bch_fs *c,
 			unsigned flags,
 			struct closure *_cl)
 {
+	struct bch_fs *c = trans->c;
 	struct bch_devs_mask devs;
 	struct open_bucket *ob;
 	struct closure *cl = NULL;
-	int ret;
 	unsigned i;
+	int ret;
 
 	rcu_read_lock();
 	devs = target_rw_devs(c, wp->data_type, target);
@@ -552,95 +944,175 @@ static int open_bucket_add_buckets(struct bch_fs *c,
 	open_bucket_for_each(c, ptrs, ob, i)
 		__clear_bit(ob->dev, devs.d);
 
+	if (erasure_code && ec_open_bucket(c, ptrs))
+		return 0;
+
+	ret = bucket_alloc_set_writepoint(c, ptrs, wp, &devs,
+				 nr_replicas, nr_effective,
+				 have_cache, erasure_code, flags);
+	if (ret)
+		return ret;
+
+	ret = bucket_alloc_set_partial(c, ptrs, wp, &devs,
+				 nr_replicas, nr_effective,
+				 have_cache, erasure_code, reserve, flags);
+	if (ret)
+		return ret;
+
 	if (erasure_code) {
-		if (!ec_open_bucket(c, ptrs)) {
-			get_buckets_from_writepoint(c, ptrs, wp, &devs,
-						    nr_replicas, nr_effective,
-						    have_cache, flags, true);
-			if (*nr_effective >= nr_replicas)
-				return 0;
+		ret = bucket_alloc_from_stripe(trans, ptrs, wp, &devs,
+					 target,
+					 nr_replicas, nr_effective,
+					 have_cache,
+					 reserve, flags, _cl);
+	} else {
+retry_blocking:
+		/*
+		 * Try nonblocking first, so that if one device is full we'll try from
+		 * other devices:
+		 */
+		ret = bch2_bucket_alloc_set_trans(trans, ptrs, &wp->stripe, &devs,
+					nr_replicas, nr_effective, have_cache,
+					flags, wp->data_type, reserve, cl);
+		if (ret &&
+		    !bch2_err_matches(ret, BCH_ERR_transaction_restart) &&
+		    !bch2_err_matches(ret, BCH_ERR_insufficient_devices) &&
+		    !cl && _cl) {
+			cl = _cl;
+			goto retry_blocking;
 		}
 
-		if (!ec_open_bucket(c, ptrs)) {
-			ret = bucket_alloc_from_stripe(c, ptrs, wp, &devs,
-						 target, erasure_code,
-						 nr_replicas, nr_effective,
-						 have_cache, flags, _cl);
-			if (ret == -FREELIST_EMPTY ||
-			    ret == -OPEN_BUCKETS_EMPTY)
-				return ret;
-			if (*nr_effective >= nr_replicas)
-				return 0;
-		}
 	}
 
-	get_buckets_from_writepoint(c, ptrs, wp, &devs,
-				    nr_replicas, nr_effective,
-				    have_cache, flags, false);
-	if (*nr_effective >= nr_replicas)
-		return 0;
+	return ret;
+}
 
-	percpu_down_read(&c->mark_lock);
-	rcu_read_lock();
+static int open_bucket_add_buckets(struct btree_trans *trans,
+			struct open_buckets *ptrs,
+			struct write_point *wp,
+			struct bch_devs_list *devs_have,
+			u16 target,
+			unsigned erasure_code,
+			unsigned nr_replicas,
+			unsigned *nr_effective,
+			bool *have_cache,
+			enum alloc_reserve reserve,
+			unsigned flags,
+			struct closure *cl)
+{
+	int ret;
 
-retry_blocking:
-	/*
-	 * Try nonblocking first, so that if one device is full we'll try from
-	 * other devices:
-	 */
-	ret = bch2_bucket_alloc_set(c, ptrs, &wp->stripe, &devs,
+	if (erasure_code) {
+		ret = __open_bucket_add_buckets(trans, ptrs, wp,
+				devs_have, target, erasure_code,
 				nr_replicas, nr_effective, have_cache,
 				reserve, flags, cl);
-	if (ret && ret != -INSUFFICIENT_DEVICES && !cl && _cl) {
-		cl = _cl;
-		goto retry_blocking;
+		if (bch2_err_matches(ret, BCH_ERR_transaction_restart) ||
+		    bch2_err_matches(ret, BCH_ERR_operation_blocked) ||
+		    bch2_err_matches(ret, BCH_ERR_freelist_empty) ||
+		    bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
+			return ret;
+		if (*nr_effective >= nr_replicas)
+			return 0;
 	}
 
-	rcu_read_unlock();
-	percpu_up_read(&c->mark_lock);
-
-	return ret;
+	ret = __open_bucket_add_buckets(trans, ptrs, wp,
+			devs_have, target, false,
+			nr_replicas, nr_effective, have_cache,
+			reserve, flags, cl);
+	return ret < 0 ? ret : 0;
 }
 
-void bch2_open_buckets_stop_dev(struct bch_fs *c, struct bch_dev *ca,
-				struct open_buckets *obs)
+static bool should_drop_bucket(struct open_bucket *ob, struct bch_fs *c,
+			       struct bch_dev *ca, bool ec)
 {
-	struct open_buckets ptrs = { .nr = 0 };
-	struct open_bucket *ob, *ob2;
-	unsigned i, j;
-
-	open_bucket_for_each(c, obs, ob, i) {
-		bool drop = !ca || ob->dev == ca->dev_idx;
+	if (ec) {
+		return ob->ec != NULL;
+	} else if (ca) {
+		bool drop = ob->dev == ca->dev_idx;
+		struct open_bucket *ob2;
+		unsigned i;
 
 		if (!drop && ob->ec) {
 			mutex_lock(&ob->ec->lock);
-			for (j = 0; j < ob->ec->new_stripe.key.v.nr_blocks; j++) {
-				if (!ob->ec->blocks[j])
+			for (i = 0; i < ob->ec->new_stripe.key.v.nr_blocks; i++) {
+				if (!ob->ec->blocks[i])
 					continue;
 
-				ob2 = c->open_buckets + ob->ec->blocks[j];
+				ob2 = c->open_buckets + ob->ec->blocks[i];
 				drop |= ob2->dev == ca->dev_idx;
 			}
 			mutex_unlock(&ob->ec->lock);
 		}
 
-		if (drop)
-			bch2_open_bucket_put(c, ob);
-		else
-			ob_push(c, &ptrs, ob);
+		return drop;
+	} else {
+		return true;
 	}
-
-	*obs = ptrs;
 }
 
-void bch2_writepoint_stop(struct bch_fs *c, struct bch_dev *ca,
-			  struct write_point *wp)
+static void bch2_writepoint_stop(struct bch_fs *c, struct bch_dev *ca,
+				 bool ec, struct write_point *wp)
 {
+	struct open_buckets ptrs = { .nr = 0 };
+	struct open_bucket *ob;
+	unsigned i;
+
 	mutex_lock(&wp->lock);
-	bch2_open_buckets_stop_dev(c, ca, &wp->ptrs);
+	open_bucket_for_each(c, &wp->ptrs, ob, i)
+		if (should_drop_bucket(ob, c, ca, ec))
+			bch2_open_bucket_put(c, ob);
+		else
+			ob_push(c, &ptrs, ob);
+	wp->ptrs = ptrs;
 	mutex_unlock(&wp->lock);
 }
 
+void bch2_open_buckets_stop(struct bch_fs *c, struct bch_dev *ca,
+			    bool ec)
+{
+	unsigned i;
+
+	/* Next, close write points that point to this device... */
+	for (i = 0; i < ARRAY_SIZE(c->write_points); i++)
+		bch2_writepoint_stop(c, ca, ec, &c->write_points[i]);
+
+	bch2_writepoint_stop(c, ca, ec, &c->copygc_write_point);
+	bch2_writepoint_stop(c, ca, ec, &c->rebalance_write_point);
+	bch2_writepoint_stop(c, ca, ec, &c->btree_write_point);
+
+	mutex_lock(&c->btree_reserve_cache_lock);
+	while (c->btree_reserve_cache_nr) {
+		struct btree_alloc *a =
+			&c->btree_reserve_cache[--c->btree_reserve_cache_nr];
+
+		bch2_open_buckets_put(c, &a->ob);
+	}
+	mutex_unlock(&c->btree_reserve_cache_lock);
+
+	spin_lock(&c->freelist_lock);
+	i = 0;
+	while (i < c->open_buckets_partial_nr) {
+		struct open_bucket *ob =
+			c->open_buckets + c->open_buckets_partial[i];
+
+		if (should_drop_bucket(ob, c, ca, ec)) {
+			--c->open_buckets_partial_nr;
+			swap(c->open_buckets_partial[i],
+			     c->open_buckets_partial[c->open_buckets_partial_nr]);
+			ob->on_partial_list = false;
+			spin_unlock(&c->freelist_lock);
+			bch2_open_bucket_put(c, ob);
+			spin_lock(&c->freelist_lock);
+		} else {
+			i++;
+		}
+	}
+	spin_unlock(&c->freelist_lock);
+
+	bch2_ec_stop_dev(c, ca);
+}
+
 static inline struct hlist_head *writepoint_hash(struct bch_fs *c,
 						 unsigned long write_point)
 {
@@ -686,8 +1158,7 @@ static bool try_increase_writepoints(struct bch_fs *c)
 	return true;
 }
 
-static bool try_decrease_writepoints(struct bch_fs *c,
-				     unsigned old_nr)
+static bool try_decrease_writepoints(struct bch_fs *c, unsigned old_nr)
 {
 	struct write_point *wp;
 
@@ -708,19 +1179,29 @@ static bool try_decrease_writepoints(struct bch_fs *c,
 	hlist_del_rcu(&wp->node);
 	mutex_unlock(&c->write_points_hash_lock);
 
-	bch2_writepoint_stop(c, NULL, wp);
+	bch2_writepoint_stop(c, NULL, false, wp);
 	return true;
 }
 
-static struct write_point *writepoint_find(struct bch_fs *c,
+static void bch2_trans_mutex_lock_norelock(struct btree_trans *trans,
+				  struct mutex *lock)
+{
+	if (!mutex_trylock(lock)) {
+		bch2_trans_unlock(trans);
+		mutex_lock(lock);
+	}
+}
+
+static struct write_point *writepoint_find(struct btree_trans *trans,
 					   unsigned long write_point)
 {
+	struct bch_fs *c = trans->c;
 	struct write_point *wp, *oldest;
 	struct hlist_head *head;
 
 	if (!(write_point & 1UL)) {
 		wp = (struct write_point *) write_point;
-		mutex_lock(&wp->lock);
+		bch2_trans_mutex_lock_norelock(trans, &wp->lock);
 		return wp;
 	}
 
@@ -729,7 +1210,7 @@ restart_find:
 	wp = __writepoint_find(head, write_point);
 	if (wp) {
 lock_wp:
-		mutex_lock(&wp->lock);
+		bch2_trans_mutex_lock_norelock(trans, &wp->lock);
 		if (wp->write_point == write_point)
 			goto out;
 		mutex_unlock(&wp->lock);
@@ -742,8 +1223,8 @@ restart_find_oldest:
 		if (!oldest || time_before64(wp->last_used, oldest->last_used))
 			oldest = wp;
 
-	mutex_lock(&oldest->lock);
-	mutex_lock(&c->write_points_hash_lock);
+	bch2_trans_mutex_lock_norelock(trans, &oldest->lock);
+	bch2_trans_mutex_lock_norelock(trans, &c->write_points_hash_lock);
 	if (oldest >= c->write_points + c->write_points_nr ||
 	    try_increase_writepoints(c)) {
 		mutex_unlock(&c->write_points_hash_lock);
@@ -764,35 +1245,35 @@ restart_find_oldest:
 	hlist_add_head_rcu(&wp->node, head);
 	mutex_unlock(&c->write_points_hash_lock);
 out:
-	wp->last_used = sched_clock();
+	wp->last_used = local_clock();
 	return wp;
 }
 
 /*
  * Get us an open_bucket we can allocate from, return with it locked:
  */
-struct write_point *bch2_alloc_sectors_start(struct bch_fs *c,
-				unsigned target,
-				unsigned erasure_code,
-				struct write_point_specifier write_point,
-				struct bch_devs_list *devs_have,
-				unsigned nr_replicas,
-				unsigned nr_replicas_required,
-				enum alloc_reserve reserve,
-				unsigned flags,
-				struct closure *cl)
+int bch2_alloc_sectors_start_trans(struct btree_trans *trans,
+			     unsigned target,
+			     unsigned erasure_code,
+			     struct write_point_specifier write_point,
+			     struct bch_devs_list *devs_have,
+			     unsigned nr_replicas,
+			     unsigned nr_replicas_required,
+			     enum alloc_reserve reserve,
+			     unsigned flags,
+			     struct closure *cl,
+			     struct write_point **wp_ret)
 {
+	struct bch_fs *c = trans->c;
 	struct write_point *wp;
 	struct open_bucket *ob;
 	struct open_buckets ptrs;
 	unsigned nr_effective, write_points_nr;
-	unsigned ob_flags = 0;
 	bool have_cache;
 	int ret;
 	int i;
 
-	if (!(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS))
-		ob_flags |= BUCKET_ALLOC_USE_DURABILITY;
+	BUG_ON(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS);
 
 	BUG_ON(!nr_replicas || !nr_replicas_required);
 retry:
@@ -801,35 +1282,44 @@ retry:
 	write_points_nr = c->write_points_nr;
 	have_cache	= false;
 
-	wp = writepoint_find(c, write_point.v);
-
-	if (wp->data_type == BCH_DATA_user)
-		ob_flags |= BUCKET_MAY_ALLOC_PARTIAL;
+	*wp_ret = wp = writepoint_find(trans, write_point.v);
 
 	/* metadata may not allocate on cache devices: */
 	if (wp->data_type != BCH_DATA_user)
 		have_cache = true;
 
-	if (!target || (flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)) {
-		ret = open_bucket_add_buckets(c, &ptrs, wp, devs_have,
+	if (target && !(flags & BCH_WRITE_ONLY_SPECIFIED_DEVS)) {
+		ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
 					      target, erasure_code,
 					      nr_replicas, &nr_effective,
 					      &have_cache, reserve,
-					      ob_flags, cl);
-	} else {
-		ret = open_bucket_add_buckets(c, &ptrs, wp, devs_have,
-					      target, erasure_code,
-					      nr_replicas, &nr_effective,
-					      &have_cache, reserve,
-					      ob_flags, NULL);
-		if (!ret)
+					      flags, NULL);
+		if (!ret ||
+		    bch2_err_matches(ret, BCH_ERR_transaction_restart))
 			goto alloc_done;
 
-		ret = open_bucket_add_buckets(c, &ptrs, wp, devs_have,
+		/* Don't retry from all devices if we're out of open buckets: */
+		if (bch2_err_matches(ret, BCH_ERR_open_buckets_empty))
+			goto allocate_blocking;
+
+		/*
+		 * Only try to allocate cache (durability = 0 devices) from the
+		 * specified target:
+		 */
+		have_cache = true;
+
+		ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
 					      0, erasure_code,
 					      nr_replicas, &nr_effective,
 					      &have_cache, reserve,
-					      ob_flags, cl);
+					      flags, cl);
+	} else {
+allocate_blocking:
+		ret = open_bucket_add_buckets(trans, &ptrs, wp, devs_have,
+					      target, erasure_code,
+					      nr_replicas, &nr_effective,
+					      &have_cache, reserve,
+					      flags, cl);
 	}
 alloc_done:
 	BUG_ON(!ret && nr_effective < nr_replicas);
@@ -837,7 +1327,7 @@ alloc_done:
 	if (erasure_code && !ec_open_bucket(c, &ptrs))
 		pr_debug("failed to get ec bucket: ret %u", ret);
 
-	if (ret == -INSUFFICIENT_DEVICES &&
+	if (ret == -BCH_ERR_insufficient_devices &&
 	    nr_effective >= nr_replicas_required)
 		ret = 0;
 
@@ -857,9 +1347,7 @@ alloc_done:
 
 	BUG_ON(!wp->sectors_free || wp->sectors_free == UINT_MAX);
 
-	verify_not_stale(c, &wp->ptrs);
-
-	return wp;
+	return 0;
 err:
 	open_bucket_for_each(c, &wp->ptrs, ob, i)
 		if (ptrs.nr < ARRAY_SIZE(ptrs.v))
@@ -870,19 +1358,17 @@ err:
 
 	mutex_unlock(&wp->lock);
 
-	if (ret == -FREELIST_EMPTY &&
+	if (bch2_err_matches(ret, BCH_ERR_freelist_empty) &&
 	    try_decrease_writepoints(c, write_points_nr))
 		goto retry;
 
-	switch (ret) {
-	case -OPEN_BUCKETS_EMPTY:
-	case -FREELIST_EMPTY:
-		return cl ? ERR_PTR(-EAGAIN) : ERR_PTR(-ENOSPC);
-	case -INSUFFICIENT_DEVICES:
-		return ERR_PTR(-EROFS);
-	default:
-		BUG();
-	}
+	if (bch2_err_matches(ret, BCH_ERR_open_buckets_empty) ||
+	    bch2_err_matches(ret, BCH_ERR_freelist_empty))
+		return cl
+			? -BCH_ERR_bucket_alloc_blocked
+			: -BCH_ERR_ENOSPC_bucket_alloc;
+
+	return ret;
 }
 
 struct bch_extent_ptr bch2_ob_ptr(struct bch_fs *c, struct open_bucket *ob)
@@ -899,34 +1385,11 @@ struct bch_extent_ptr bch2_ob_ptr(struct bch_fs *c, struct open_bucket *ob)
 	};
 }
 
-/*
- * Append pointers to the space we just allocated to @k, and mark @sectors space
- * as allocated out of @ob
- */
 void bch2_alloc_sectors_append_ptrs(struct bch_fs *c, struct write_point *wp,
 				    struct bkey_i *k, unsigned sectors,
 				    bool cached)
-
 {
-	struct open_bucket *ob;
-	unsigned i;
-
-	BUG_ON(sectors > wp->sectors_free);
-	wp->sectors_free -= sectors;
-
-	open_bucket_for_each(c, &wp->ptrs, ob, i) {
-		struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
-		struct bch_extent_ptr ptr = bch2_ob_ptr(c, ob);
-
-		ptr.cached = cached ||
-			(!ca->mi.durability &&
-			 wp->data_type == BCH_DATA_user);
-
-		bch2_bkey_append_ptr(k, ptr);
-
-		BUG_ON(sectors > ob->sectors_free);
-		ob->sectors_free -= sectors;
-	}
+	bch2_alloc_sectors_append_ptrs_inlined(c, wp, k, sectors, cached);
 }
 
 /*
@@ -935,17 +1398,7 @@ void bch2_alloc_sectors_append_ptrs(struct bch_fs *c, struct write_point *wp,
  */
 void bch2_alloc_sectors_done(struct bch_fs *c, struct write_point *wp)
 {
-	struct open_buckets ptrs = { .nr = 0 }, keep = { .nr = 0 };
-	struct open_bucket *ob;
-	unsigned i;
-
-	open_bucket_for_each(c, &wp->ptrs, ob, i)
-		ob_push(c, !ob->sectors_free ? &ptrs : &keep, ob);
-	wp->ptrs = keep;
-
-	mutex_unlock(&wp->lock);
-
-	bch2_open_buckets_put(c, &ptrs);
+	bch2_alloc_sectors_done_inlined(c, wp);
 }
 
 static inline void writepoint_init(struct write_point *wp,
@@ -953,6 +1406,10 @@ static inline void writepoint_init(struct write_point *wp,
 {
 	mutex_init(&wp->lock);
 	wp->data_type = type;
+
+	INIT_WORK(&wp->index_update_work, bch2_write_point_do_index_updates);
+	INIT_LIST_HEAD(&wp->writes);
+	spin_lock_init(&wp->writes_lock);
 }
 
 void bch2_fs_allocator_foreground_init(struct bch_fs *c)
@@ -983,28 +1440,91 @@ void bch2_fs_allocator_foreground_init(struct bch_fs *c)
 	     wp < c->write_points + c->write_points_nr; wp++) {
 		writepoint_init(wp, BCH_DATA_user);
 
-		wp->last_used	= sched_clock();
+		wp->last_used	= local_clock();
 		wp->write_point	= (unsigned long) wp;
 		hlist_add_head_rcu(&wp->node,
 				   writepoint_hash(c, wp->write_point));
 	}
 }
 
+static void bch2_open_bucket_to_text(struct printbuf *out, struct bch_fs *c, struct open_bucket *ob)
+{
+	struct bch_dev *ca = bch_dev_bkey_exists(c, ob->dev);
+	unsigned data_type = ob->data_type;
+	barrier(); /* READ_ONCE() doesn't work on bitfields */
+
+	prt_printf(out, "%zu ref %u %s %u:%llu gen %u allocated %u/%u",
+		   ob - c->open_buckets,
+		   atomic_read(&ob->pin),
+		   data_type < BCH_DATA_NR ? bch2_data_types[data_type] : "invalid data type",
+		   ob->dev, ob->bucket, ob->gen,
+		   ca->mi.bucket_size - ob->sectors_free, ca->mi.bucket_size);
+	if (ob->ec)
+		prt_printf(out, " ec idx %llu", ob->ec->idx);
+	if (ob->on_partial_list)
+		prt_str(out, " partial");
+	prt_newline(out);
+}
+
 void bch2_open_buckets_to_text(struct printbuf *out, struct bch_fs *c)
 {
 	struct open_bucket *ob;
 
+	out->atomic++;
+
 	for (ob = c->open_buckets;
 	     ob < c->open_buckets + ARRAY_SIZE(c->open_buckets);
 	     ob++) {
 		spin_lock(&ob->lock);
-		if (ob->valid && !ob->on_partial_list) {
-			pr_buf(out, "%zu ref %u type %s\n",
-			       ob - c->open_buckets,
-			       atomic_read(&ob->pin),
-			       bch2_data_types[ob->data_type]);
-		}
+		if (ob->valid && !ob->on_partial_list)
+			bch2_open_bucket_to_text(out, c, ob);
 		spin_unlock(&ob->lock);
 	}
 
+	--out->atomic;
+}
+
+void bch2_open_buckets_partial_to_text(struct printbuf *out, struct bch_fs *c)
+{
+	unsigned i;
+
+	out->atomic++;
+	spin_lock(&c->freelist_lock);
+
+	for (i = 0; i < c->open_buckets_partial_nr; i++)
+		bch2_open_bucket_to_text(out, c,
+				c->open_buckets + c->open_buckets_partial[i]);
+
+	spin_unlock(&c->freelist_lock);
+	--out->atomic;
+}
+
+static const char * const bch2_write_point_states[] = {
+#define x(n)	#n,
+	WRITE_POINT_STATES()
+#undef x
+	NULL
+};
+
+void bch2_write_points_to_text(struct printbuf *out, struct bch_fs *c)
+{
+	struct write_point *wp;
+	unsigned i;
+
+	for (wp = c->write_points;
+	     wp < c->write_points + ARRAY_SIZE(c->write_points);
+	     wp++) {
+		prt_printf(out, "%lu: ", wp->write_point);
+		prt_human_readable_u64(out, wp->sectors_allocated);
+
+		prt_printf(out, " last wrote: ");
+		bch2_pr_time_units(out, sched_clock() - wp->last_used);
+
+		for (i = 0; i < WRITE_POINT_STATE_NR; i++) {
+			prt_printf(out, " %s: ", bch2_write_point_states[i]);
+			bch2_pr_time_units(out, wp->time[i]);
+		}
+
+		prt_newline(out);
+	}
 }