[PATCH RFC] xfs: Print XFS UUID on mount and umount events.

[PATCH RFC] xfs: Print XFS UUID on mount and umount events.

[Lukas Herbolt]

As of now only device names are pritend out over __xfs_printk().
The device names are not persistent across reboots which in case
of searching for origin of corruption brings another task to properly
indetify the devices. This patch add XFS UUID upon every mount/umount
event which will make the identification much easier.

Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
---
 fs/xfs/xfs_log.c   | 8 ++++----
 fs/xfs/xfs_super.c | 2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 16114a203bcb6..79d1d2838dec3 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -646,12 +646,12 @@ xfs_log_mount(
 	int		min_logfsbs;
 
 	if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
-		xfs_notice(mp, "Mounting V%d Filesystem",
-			   XFS_SB_VERSION_NUM(&mp->m_sb));
+		xfs_notice(mp, "Mounting V%d Filesystem %pU",
+			   XFS_SB_VERSION_NUM(&mp->m_sb), (void *)&mp->m_sb.sb_uuid);
 	} else {
 		xfs_notice(mp,
-"Mounting V%d filesystem in no-recovery mode. Filesystem will be inconsistent.",
-			   XFS_SB_VERSION_NUM(&mp->m_sb));
+"Mounting V%d filesystem %pU in no-recovery mode. Filesystem will be inconsistent.",
+			   XFS_SB_VERSION_NUM(&mp->m_sb), (void *)&mp->m_sb.sb_uuid);
 		ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
 	}
 
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 6d8a0f805dae0..9f1b33a002fd5 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1063,7 +1063,7 @@ xfs_fs_put_super(
 	if (!sb->s_fs_info)
 		return;
 
-	xfs_notice(mp, "Unmounting Filesystem");
+	xfs_notice(mp, "Unmounting Filesystem %pU", (void *)&mp->m_sb.sb_uuid);
 	xfs_filestream_unmount(mp);
 	xfs_unmountfs(mp);
 
-- 
2.31.1

Re: [PATCH RFC] xfs: Print XFS UUID on mount and umount events.

[Christoph Hellwig]

On Wed, May 19, 2021 at 11:37:52AM +0200, Lukas Herbolt wrote:
> As of now only device names are pritend out over __xfs_printk().
> The device names are not persistent across reboots which in case
> of searching for origin of corruption brings another task to properly
> indetify the devices. This patch add XFS UUID upon every mount/umount
> event which will make the identification much easier.

This looks sensible, but please avoid the pointless casts and overly
long lines.  i.e. something like this:

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index c19a82adea1edb..2089177168f487 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -572,12 +572,14 @@ xfs_log_mount(
 	int		min_logfsbs;
 
 	if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) {
-		xfs_notice(mp, "Mounting V%d Filesystem",
-			   XFS_SB_VERSION_NUM(&mp->m_sb));
+		xfs_notice(mp, "Mounting V%d Filesystem %pU",
+			   XFS_SB_VERSION_NUM(&mp->m_sb),
+			   &mp->m_sb.sb_uuid);
 	} else {
 		xfs_notice(mp,
-"Mounting V%d filesystem in no-recovery mode. Filesystem will be inconsistent.",
-			   XFS_SB_VERSION_NUM(&mp->m_sb));
+"Mounting V%d filesystem %pU in no-recovery mode. Filesystem will be inconsistent.",
+			   XFS_SB_VERSION_NUM(&mp->m_sb),
+			   &mp->m_sb.sb_uuid);
 		ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
 	}
 
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index f7f70438d98703..fa4589d391a892 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1043,7 +1043,7 @@ xfs_fs_put_super(
 	if (!sb->s_fs_info)
 		return;
 
-	xfs_notice(mp, "Unmounting Filesystem");
+	xfs_notice(mp, "Unmounting Filesystem %pU", &mp->m_sb.sb_uuid);
 	xfs_filestream_unmount(mp);
 	xfs_unmountfs(mp);