bcachefs: for_each_rw_member_rcu()

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

6 files changed, 21 insertions, 9 deletions

diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index 0494d188605f..195d20220b7d 100644
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -2575,8 +2575,10 @@ u64 bch2_min_rw_member_capacity(struct bch_fs *c)
 {
 	u64 ret = U64_MAX;
 
-	for_each_rw_member(c, ca)
+	rcu_read_lock();
+	for_each_rw_member_rcu(c, ca)
 		ret = min(ret, ca->mi.nbuckets * ca->mi.bucket_size);
+	rcu_read_unlock();
 	return ret;
 }
 
@@ -2600,8 +2602,12 @@ static bool bch2_dev_has_open_write_point(struct bch_fs *c, struct bch_dev *ca)
 
 void bch2_dev_allocator_set_rw(struct bch_fs *c, struct bch_dev *ca, bool rw)
 {
+	/* BCH_DATA_free == all rw devs */
+
 	for (unsigned i = 0; i < ARRAY_SIZE(c->rw_devs); i++)
-		if (rw && (ca->mi.data_allowed & BIT(i)))
+		if (rw &&
+		    (i == BCH_DATA_free ||
+		     (ca->mi.data_allowed & BIT(i))))
 			set_bit(ca->dev_idx, c->rw_devs[i].d);
 		else
 			clear_bit(ca->dev_idx, c->rw_devs[i].d);
diff --git a/fs/bcachefs/journal.c b/fs/bcachefs/journal.c
index 3694b83af8cc..e1cd6e8e37cf 100644
--- a/fs/bcachefs/journal.c
+++ b/fs/bcachefs/journal.c
@@ -699,8 +699,10 @@ static unsigned max_dev_latency(struct bch_fs *c)
 {
 	u64 nsecs = 0;
 
-	for_each_rw_member(c, ca)
+	rcu_read_lock();
+	for_each_rw_member_rcu(c, ca)
 		nsecs = max(nsecs, ca->io_latency[WRITE].stats.max_duration);
+	rcu_read_unlock();
 
 	return nsecs_to_jiffies(nsecs);
 }
diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index 28fa381cd589..438ad32ba242 100644
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -2055,12 +2055,9 @@ CLOSURE_CALLBACK(bch2_journal_write)
 	struct journal *j = container_of(w, struct journal, buf[w->idx]);
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
 	struct bch_replicas_padded replicas;
-	unsigned nr_rw_members = 0;
+	unsigned nr_rw_members = dev_mask_nr(&c->rw_devs[BCH_DATA_journal]);
 	int ret;
 
-	for_each_rw_member(c, ca)
-		nr_rw_members++;
-
 	BUG_ON(BCH_SB_CLEAN(c->disk_sb.sb));
 	BUG_ON(!w->write_started);
 	BUG_ON(w->write_allocated);
diff --git a/fs/bcachefs/journal_reclaim.c b/fs/bcachefs/journal_reclaim.c
index fd7a140c9fd6..dc8169a970dd 100644
--- a/fs/bcachefs/journal_reclaim.c
+++ b/fs/bcachefs/journal_reclaim.c
@@ -627,7 +627,8 @@ static u64 journal_seq_to_flush(struct journal *j)
 
 	spin_lock(&j->lock);
 
-	for_each_rw_member(c, ca) {
+	rcu_read_lock();
+	for_each_rw_member_rcu(c, ca) {
 		struct journal_device *ja = &ca->journal;
 		unsigned nr_buckets, bucket_to_flush;
 
@@ -641,6 +642,7 @@ static u64 journal_seq_to_flush(struct journal *j)
 		seq_to_flush = max(seq_to_flush,
 				   ja->bucket_seq[bucket_to_flush]);
 	}
+	rcu_read_unlock();
 
 	/* Also flush if the pin fifo is more than half full */
 	seq_to_flush = max_t(s64, seq_to_flush,
diff --git a/fs/bcachefs/movinggc.c b/fs/bcachefs/movinggc.c
index 96873372b516..e97e87ebe312 100644
--- a/fs/bcachefs/movinggc.c
+++ b/fs/bcachefs/movinggc.c
@@ -279,7 +279,8 @@ unsigned long bch2_copygc_wait_amount(struct bch_fs *c)
 {
 	s64 wait = S64_MAX, fragmented_allowed, fragmented;
 
-	for_each_rw_member(c, ca) {
+	rcu_read_lock();
+	for_each_rw_member_rcu(c, ca) {
 		struct bch_dev_usage_full usage_full = bch2_dev_usage_full_read(ca);
 		struct bch_dev_usage usage;
 
@@ -296,6 +297,7 @@ unsigned long bch2_copygc_wait_amount(struct bch_fs *c)
 
 		wait = min(wait, max(0LL, fragmented_allowed - fragmented));
 	}
+	rcu_read_unlock();
 
 	return wait;
 }
diff --git a/fs/bcachefs/sb-members.h b/fs/bcachefs/sb-members.h
index 28c6fc25c32c..c71a1ba61525 100644
--- a/fs/bcachefs/sb-members.h
+++ b/fs/bcachefs/sb-members.h
@@ -107,6 +107,9 @@ static inline struct bch_dev *__bch2_next_dev(struct bch_fs *c, struct bch_dev *
 #define for_each_online_member_rcu(_c, _ca)				\
 	for_each_member_device_rcu(_c, _ca, &(_c)->online_devs)
 
+#define for_each_rw_member_rcu(_c, _ca)					\
+	for_each_member_device_rcu(_c, _ca, &(_c)->rw_devs[BCH_DATA_free])
+
 static inline void bch2_dev_get(struct bch_dev *ca)
 {
 #ifdef CONFIG_BCACHEFS_DEBUG