xfs: hook live rmap operations during a repair operationrepair-rmap-btree_2022-11-09

Hook the regular rmap code when an rmapbt repair operation is running so
that we can unlock the AGF buffer to scan the filesystem and keep the
in-memory btree up to date during the scan.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>

1 files changed, 36 insertions, 0 deletions

diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
index 532eebb79605..56422e5bde38 100644
--- a/fs/xfs/scrub/repair.c
+++ b/fs/xfs/scrub/repair.c
@@ -1127,3 +1127,39 @@ xrep_metadata_inode_forks(
 
 	return 0;
 }
+
+/*
+ * Create a dummy transaction for use in a live update hook function.  This
+ * function MUST NOT be called from regular repair code because the current
+ * process' transaction is saved via the cookie.
+ */
+int
+xrep_trans_alloc_hook_dummy(
+	struct xfs_mount	*mp,
+	void			**cookiep,
+	struct xfs_trans	**tpp)
+{
+	int			error;
+
+	*cookiep = current->journal_info;
+	current->journal_info = NULL;
+
+	error = xfs_trans_alloc_empty(mp, tpp);
+	if (!error)
+		return 0;
+
+	current->journal_info = *cookiep;
+	*cookiep = NULL;
+	return error;
+}
+
+/* Cancel a dummy transaction used by a live update hook function. */
+void
+xrep_trans_cancel_hook_dummy(
+	void			**cookiep,
+	struct xfs_trans	*tp)
+{
+	xfs_trans_cancel(tp);
+	current->journal_info = *cookiep;
+	*cookiep = NULL;
+}