bcachefs: Redo checks for sufficient devices

When the replicas mechanism was added, for tracking data by which drives
it's replicated on, the check for whether we have sufficient devices was
never updated to make use of it. This patch finally does that.

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

1 files changed, 26 insertions, 72 deletions

diff --git a/fs/bcachefs/replicas.c b/fs/bcachefs/replicas.c
index bf1804c10bfb..8003973b0400 100644
--- a/fs/bcachefs/replicas.c
+++ b/fs/bcachefs/replicas.c
@@ -967,94 +967,48 @@ const struct bch_sb_field_ops bch_sb_field_ops_replicas_v0 = {
 
 /* Query replicas: */
 
-struct replicas_status __bch2_replicas_status(struct bch_fs *c,
-					      struct bch_devs_mask online_devs)
+bool bch2_have_enough_devs(struct bch_fs *c, struct bch_devs_mask devs,
+			   unsigned flags, bool print)
 {
-	struct bch_sb_field_members *mi;
 	struct bch_replicas_entry *e;
-	unsigned i, nr_online, nr_offline;
-	struct replicas_status ret;
-
-	memset(&ret, 0, sizeof(ret));
-
-	for (i = 0; i < ARRAY_SIZE(ret.replicas); i++)
-		ret.replicas[i].redundancy = INT_MAX;
-
-	mi = bch2_sb_get_members(c->disk_sb.sb);
+	bool ret = true;
 
 	percpu_down_read(&c->mark_lock);
-
 	for_each_cpu_replicas_entry(&c->replicas, e) {
-		if (e->data_type >= ARRAY_SIZE(ret.replicas))
-			panic("e %p data_type %u\n", e, e->data_type);
+		unsigned i, nr_online = 0, dflags = 0;
+		bool metadata = e->data_type < BCH_DATA_user;
 
-		nr_online = nr_offline = 0;
+		for (i = 0; i < e->nr_devs; i++)
+			nr_online += test_bit(e->devs[i], devs.d);
 
-		for (i = 0; i < e->nr_devs; i++) {
-			BUG_ON(!bch2_dev_exists(c->disk_sb.sb, mi,
-						e->devs[i]));
+		if (nr_online < e->nr_required)
+			dflags |= metadata
+				? BCH_FORCE_IF_METADATA_LOST
+				: BCH_FORCE_IF_DATA_LOST;
 
-			if (test_bit(e->devs[i], online_devs.d))
-				nr_online++;
-			else
-				nr_offline++;
-		}
+		if (nr_online < e->nr_devs)
+			dflags |= metadata
+				? BCH_FORCE_IF_METADATA_DEGRADED
+				: BCH_FORCE_IF_DATA_DEGRADED;
 
-		ret.replicas[e->data_type].redundancy =
-			min(ret.replicas[e->data_type].redundancy,
-			    (int) nr_online - (int) e->nr_required);
+		if (dflags & ~flags) {
+			if (print) {
+				char buf[100];
 
-		ret.replicas[e->data_type].nr_offline =
-			max(ret.replicas[e->data_type].nr_offline,
-			    nr_offline);
-	}
+				bch2_replicas_entry_to_text(&PBUF(buf), e);
+				bch_err(c, "insufficient devices online (%u) for replicas entry %s",
+					nr_online, buf);
+			}
+			ret = false;
+			break;
+		}
 
+	}
 	percpu_up_read(&c->mark_lock);
 
-	for (i = 0; i < ARRAY_SIZE(ret.replicas); i++)
-		if (ret.replicas[i].redundancy == INT_MAX)
-			ret.replicas[i].redundancy = 0;
-
 	return ret;
 }
 
-struct replicas_status bch2_replicas_status(struct bch_fs *c)
-{
-	return __bch2_replicas_status(c, bch2_online_devs(c));
-}
-
-static bool have_enough_devs(struct replicas_status s,
-			     enum bch_data_type type,
-			     bool force_if_degraded,
-			     bool force_if_lost)
-{
-	return (!s.replicas[type].nr_offline || force_if_degraded) &&
-		(s.replicas[type].redundancy >= 0 || force_if_lost);
-}
-
-bool bch2_have_enough_devs(struct replicas_status s, unsigned flags)
-{
-	return (have_enough_devs(s, BCH_DATA_journal,
-				 flags & BCH_FORCE_IF_METADATA_DEGRADED,
-				 flags & BCH_FORCE_IF_METADATA_LOST) &&
-		have_enough_devs(s, BCH_DATA_btree,
-				 flags & BCH_FORCE_IF_METADATA_DEGRADED,
-				 flags & BCH_FORCE_IF_METADATA_LOST) &&
-		have_enough_devs(s, BCH_DATA_user,
-				 flags & BCH_FORCE_IF_DATA_DEGRADED,
-				 flags & BCH_FORCE_IF_DATA_LOST));
-}
-
-int bch2_replicas_online(struct bch_fs *c, bool meta)
-{
-	struct replicas_status s = bch2_replicas_status(c);
-
-	return (meta
-		? min(s.replicas[BCH_DATA_journal].redundancy,
-		      s.replicas[BCH_DATA_btree].redundancy)
-		: s.replicas[BCH_DATA_user].redundancy) + 1;
-}
-
 unsigned bch2_dev_has_data(struct bch_fs *c, struct bch_dev *ca)
 {
 	struct bch_replicas_entry *e;