From: Darrick J. Wong <darrick.wong@oracle.com>
Date: Wed, 30 Sep 2020 16:45:13 +0000 (-0400)
Subject: libxfs: disallow filesystems with reverse mapping and reflink and realtime
X-Git-Tag: xfsprogs-5.9-fixes2_2020-10-10~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4aaeedc4a1cc52f8bc49dfc9c89704aff92b7c5e;p=thirdparty%2Fxfsprogs-dev.git

libxfs: disallow filesystems with reverse mapping and reflink and realtime

Neither the kernel nor the code in xfsprogs support filesystems that
have (either reverse mapping btrees or reflink) enabled and a realtime
volume configured.  The kernel rejects such combinations and mkfs
refuses to format such a config, but xfsprogs doesn't check and can do
Bad Things, so port those checks before someone shreds their filesystem.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
---

diff --git a/libxfs/init.c b/libxfs/init.c
index cb8967bc7..330c64519 100644
--- a/libxfs/init.c
+++ b/libxfs/init.c
@@ -428,6 +428,21 @@ rtmount_init(
 	sbp = &mp->m_sb;
 	if (sbp->sb_rblocks == 0)
 		return 0;
+
+	if (xfs_sb_version_hasreflink(sbp)) {
+		fprintf(stderr,
+	_("%s: Reflink not compatible with realtime device. Please try a newer xfsprogs.\n"),
+				progname);
+		return -1;
+	}
+
+	if (xfs_sb_version_hasrmapbt(sbp)) {
+		fprintf(stderr,
+	_("%s: Reverse mapping btree not compatible with realtime device. Please try a newer xfsprogs.\n"),
+				progname);
+		return -1;
+	}
+
 	if (mp->m_rtdev_targp->dev == 0 && !(flags & LIBXFS_MOUNT_DEBUGGER)) {
 		fprintf(stderr, _("%s: filesystem has a realtime subvolume\n"),
 			progname);