From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Sat, 18 Jan 2025 00:26:10 +0000 (-0500)
Subject: bcachefs: Don't start promotes from bch2_rbio_free()
X-Git-Tag: v6.15-rc1~146^2~154
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4dfb76e0ad22d959ecb477f1e982500047ce38a4;p=thirdparty%2Fkernel%2Flinux.git

bcachefs: Don't start promotes from bch2_rbio_free()

we don't want to block completion of the read - starting a promote calls
into the write path, which will block.

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

diff --git a/fs/bcachefs/io_read.c b/fs/bcachefs/io_read.c
index bdb554f6db8c6..15494aba4547b 100644
--- a/fs/bcachefs/io_read.c
+++ b/fs/bcachefs/io_read.c
@@ -80,6 +80,7 @@ struct promote_op {
 	struct rhash_head	hash;
 	struct bpos		pos;
 
+	struct work_struct	work;
 	struct data_update	write;
 	struct bio_vec		bi_inline_vecs[]; /* must be last */
 };
@@ -149,13 +150,21 @@ static void promote_done(struct bch_write_op *wop)
 	promote_free(&op->write.rbio);
 }
 
+static void promote_start_work(struct work_struct *work)
+{
+	struct promote_op *op = container_of(work, struct promote_op, work);
+
+	bch2_data_update_read_done(&op->write);
+}
+
 static noinline void promote_start(struct bch_read_bio *rbio)
 {
 	struct promote_op *op = container_of(rbio, struct promote_op, write.rbio);
 
 	trace_and_count(op->write.op.c, read_promote, &rbio->bio);
 
-	bch2_data_update_read_done(&op->write);
+	INIT_WORK(&op->work, promote_start_work);
+	queue_work(rbio->c->write_ref_wq, &op->work);
 }
 
 static struct bch_read_bio *__promote_alloc(struct btree_trans *trans,