From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Wed, 28 May 2025 00:37:50 +0000 (-0400)
Subject: bcachefs: Fix incorrect multiple dev check in journal write path
X-Git-Tag: v6.16-rc1~48^2~55
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=813825d24135aa3109cf7746ce11f1ec2ab901fd;p=thirdparty%2Fkernel%2Flinux.git

bcachefs: Fix incorrect multiple dev check in journal write path

It's uncomon to have multiple devices with journalling only on a subset,
but can be specified with the 'data_allowed' option. We need to know if
we're doing data/metadata writes to multiple devices, as that requires
issuing flushes before the journal writes.

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

diff --git a/fs/bcachefs/journal_io.c b/fs/bcachefs/journal_io.c
index 30122abf3e2c7..527ce6f74b630 100644
--- a/fs/bcachefs/journal_io.c
+++ b/fs/bcachefs/journal_io.c
@@ -1635,6 +1635,16 @@ retry_alloc:
 done:
 	BUG_ON(bkey_val_u64s(&w->key.k) > BCH_REPLICAS_MAX);
 
+#if 0
+	/*
+	 * XXX: we need a way to alert the user when we go degraded for any
+	 * reason
+	 */
+	if (*replicas < min(replicas_want,
+			    dev_mask_nr(&c->rw_devs[BCH_DATA_free]))) {
+	}
+#endif
+
 	return *replicas >= replicas_need ? 0 : -BCH_ERR_insufficient_journal_devices;
 }
 
@@ -2112,7 +2122,7 @@ 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);
 	union bch_replicas_padded replicas;
-	unsigned nr_rw_members = dev_mask_nr(&c->rw_devs[BCH_DATA_journal]);
+	unsigned nr_rw_members = dev_mask_nr(&c->rw_devs[BCH_DATA_free]);
 	int ret;
 
 	BUG_ON(BCH_SB_CLEAN(c->disk_sb.sb));