[PATCH 3/3] bcachefs: Incompatible features may now be enabled at runtime

[Kent Overstreet <kent.overstreet@linux.dev>]

version_upgrade is now a runtime option.

In the future we'll want to add compatible upgrades at runtime, and call
the full check_version_upgrade() when the option changes, but we don't
have compatible optional upgrades just yet.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
---
 fs/bcachefs/opts.c     |  9 +++++++++
 fs/bcachefs/opts.h     |  2 +-
 fs/bcachefs/recovery.c |  4 ++--
 fs/bcachefs/super-io.c | 25 +++++++++++++++++++++++++
 fs/bcachefs/super-io.h |  1 +
 5 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/fs/bcachefs/opts.c b/fs/bcachefs/opts.c
index 386482ff8e7b..b1cf88905b81 100644
--- a/fs/bcachefs/opts.c
+++ b/fs/bcachefs/opts.c
@@ -595,6 +595,15 @@ void bch2_opt_hook_post_set(struct bch_fs *c, struct bch_dev *ca, u64 inum,
 			mutex_unlock(&c->sb_lock);
 		}
 		break;
+	case Opt_version_upgrade:
+		/*
+		 * XXX: in the future we'll likely want to do compatible
+		 * upgrades at runtime as well, but right now there's nothing
+		 * that does that:
+		 */
+		if (new_opts->version_upgrade == BCH_VERSION_UPGRADE_incompatible)
+			bch2_sb_upgrade_incompat(c);
+		break;
 	default:
 		break;
 	}
diff --git a/fs/bcachefs/opts.h b/fs/bcachefs/opts.h
index f69ba5e63e15..5cdb18802138 100644
--- a/fs/bcachefs/opts.h
+++ b/fs/bcachefs/opts.h
@@ -445,7 +445,7 @@ enum fsck_err_opts {
 	  BCH2_NO_SB_OPT,		false,				\
 	  NULL,		"Reconstruct alloc btree")			\
 	x(version_upgrade,		u8,				\
-	  OPT_FS|OPT_MOUNT,						\
+	  OPT_FS|OPT_MOUNT|OPT_RUNTIME,					\
 	  OPT_STR(bch2_version_upgrade_opts),				\
 	  BCH_SB_VERSION_UPGRADE,	BCH_VERSION_UPGRADE_compatible,	\
 	  NULL,		"Set superblock to latest version,\n"		\
diff --git a/fs/bcachefs/recovery.c b/fs/bcachefs/recovery.c
index 606d684e6f23..58ee1ebdcbaa 100644
--- a/fs/bcachefs/recovery.c
+++ b/fs/bcachefs/recovery.c
@@ -666,7 +666,7 @@ static bool check_version_upgrade(struct bch_fs *c)
 				     bch2_recovery_passes_from_stable(le64_to_cpu(passes)));
 		}
 
-		bch_info(c, "%s", buf.buf);
+		bch_notice(c, "%s", buf.buf);
 		printbuf_exit(&buf);
 
 		ret = true;
@@ -682,7 +682,7 @@ static bool check_version_upgrade(struct bch_fs *c)
 		bch2_version_to_text(&buf, c->sb.version_incompat_allowed);
 		prt_newline(&buf);
 
-		bch_info(c, "%s", buf.buf);
+		bch_notice(c, "%s", buf.buf);
 		printbuf_exit(&buf);
 
 		ret = true;
diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
index fa4d323ddada..791dee30f042 100644
--- a/fs/bcachefs/super-io.c
+++ b/fs/bcachefs/super-io.c
@@ -1273,6 +1273,31 @@ void bch2_sb_upgrade(struct bch_fs *c, unsigned new_version, bool incompat)
 	}
 }
 
+void bch2_sb_upgrade_incompat(struct bch_fs *c)
+{
+	mutex_lock(&c->sb_lock);
+	if (c->sb.version == c->sb.version_incompat_allowed)
+		goto unlock;
+
+	struct printbuf buf = PRINTBUF;
+
+	prt_str(&buf, "Now allowing incompatible features up to ");
+	bch2_version_to_text(&buf, c->sb.version);
+	prt_str(&buf, ", previously allowed up to ");
+	bch2_version_to_text(&buf, c->sb.version_incompat_allowed);
+	prt_newline(&buf);
+
+	bch_notice(c, "%s", buf.buf);
+	printbuf_exit(&buf);
+
+	c->disk_sb.sb->features[0] |= cpu_to_le64(BCH_SB_FEATURES_ALL);
+	SET_BCH_SB_VERSION_INCOMPAT_ALLOWED(c->disk_sb.sb,
+			max(BCH_SB_VERSION_INCOMPAT_ALLOWED(c->disk_sb.sb), c->sb.version));
+	bch2_write_super(c);
+unlock:
+	mutex_unlock(&c->sb_lock);
+}
+
 static int bch2_sb_ext_validate(struct bch_sb *sb, struct bch_sb_field *f,
 				enum bch_validate_flags flags, struct printbuf *err)
 {
diff --git a/fs/bcachefs/super-io.h b/fs/bcachefs/super-io.h
index 78f708a6fbcd..a3b7a90f2533 100644
--- a/fs/bcachefs/super-io.h
+++ b/fs/bcachefs/super-io.h
@@ -107,6 +107,7 @@ static inline void bch2_check_set_feature(struct bch_fs *c, unsigned feat)
 
 bool bch2_check_version_downgrade(struct bch_fs *);
 void bch2_sb_upgrade(struct bch_fs *, unsigned, bool);
+void bch2_sb_upgrade_incompat(struct bch_fs *);
 
 void __bch2_sb_field_to_text(struct printbuf *, struct bch_sb *,
 			     struct bch_sb_field *);
-- 
2.49.0