[PATCH] xfs: return -EINVAL instead of -EUCLEAN when mounting non-xfs

[Sergei Trofimovich]

It fixes boot panic when trying to boot from btrfs filesystem.
kernel tries to mount as xfs and gets fatal -EUCLEAN:

[    0.170000] VFS: Cannot open root device "ubda" or unknown-block(98,0): error -117
[    0.170000] Please append a correct "root=" boot option; here are the available partitions:
[    0.170000] 6200         1048576 ubda  driver: uml-blkdev
[    0.170000] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(98,0)

init/do_mounts.c expects only -EINVAL as 'retry another' option.
Fixes regression introduced by commit 98021821a502db347bd9c7671beeee6e8ce07ea6

Signed-off-by: Sergei Trofimovich <slyfox at gentoo.org>
CC: Ben Myers <bpm at sgi.com>
CC: Alex Elder <elder at kernel.org>
CC: xfs at oss.sgi.com
CC: linux-kernel at vger.kernel.org
CC: Dave Chinner <dchinner at redhat.com>
CC: Phil White <pwhite at sgi.com>
---
 fs/xfs/xfs_mount.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index da50846..379cac1 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -641,41 +641,41 @@ xfs_sb_read_verify(
 /*
  * We may be probed for a filesystem match, so we may not want to emit
  * messages when the superblock buffer is not actually an XFS superblock.
  * If we find an XFS superblock, the run a normal, noisy mount because we are
  * really going to mount it and want to know about errors.
  */
 static void
 xfs_sb_quiet_read_verify(
 	struct xfs_buf	*bp)
 {
 	struct xfs_sb	sb;
 
 	xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp));
 
 	if (sb.sb_magicnum == XFS_SB_MAGIC) {
 		/* XFS filesystem, verify noisily! */
 		xfs_sb_read_verify(bp);
 		return;
 	}
 	/* quietly fail */
-	xfs_buf_ioerror(bp, EFSCORRUPTED);
+	xfs_buf_ioerror(bp, EINVAL);
 }
 
 static void
 xfs_sb_write_verify(
 	struct xfs_buf	*bp)
 {
 	xfs_sb_verify(bp);
 }
 
 const struct xfs_buf_ops xfs_sb_buf_ops = {
 	.verify_read = xfs_sb_read_verify,
 	.verify_write = xfs_sb_write_verify,
 };
 
 static const struct xfs_buf_ops xfs_sb_quiet_buf_ops = {
 	.verify_read = xfs_sb_quiet_read_verify,
 	.verify_write = xfs_sb_write_verify,
 };
 
 /*
-- 
1.8.0.2