From c0788c1f211383d7e1f3460cc997c9edbe7f3fe9 Mon Sep 17 00:00:00 2001
From: Yecheng Fu <fuyecheng@pingcap.com>
Date: Sun, 27 Oct 2019 15:55:07 +0800
Subject: [PATCH] Update GetMountRefs comments

---
 pkg/util/mount/mount.go       | 2 +-
 pkg/util/mount/mount_linux.go | 5 +++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/pkg/util/mount/mount.go b/pkg/util/mount/mount.go
index 7324d691144..7d94a48f4b0 100644
--- a/pkg/util/mount/mount.go
+++ b/pkg/util/mount/mount.go
@@ -48,7 +48,7 @@ type Interface interface {
 	// most notably linux bind mounts and symbolic link.
 	IsLikelyNotMountPoint(file string) (bool, error)
 	// GetMountRefs finds all mount references to the path, returns a
-	// list of paths. Path could be a mountpoint path, device or a normal
+	// list of paths. Path could be a mountpoint or a normal
 	// directory (for bind mount).
 	GetMountRefs(pathname string) ([]string, error)
 }
diff --git a/pkg/util/mount/mount_linux.go b/pkg/util/mount/mount_linux.go
index dfd52bfe105..c0c4b0dd823 100644
--- a/pkg/util/mount/mount_linux.go
+++ b/pkg/util/mount/mount_linux.go
@@ -238,7 +238,7 @@ func (mounter *Mounter) IsLikelyNotMountPoint(file string) (bool, error) {
 }
 
 // GetMountRefs finds all mount references to pathname, returns a
-// list of paths. Path could be a mountpoint path, device or a normal
+// list of paths. Path could be a mountpoint or a normal
 // directory (for bind mount).
 func (mounter *Mounter) GetMountRefs(pathname string) ([]string, error) {
 	pathExists, pathErr := PathExists(pathname)
@@ -441,7 +441,8 @@ func parseProcMounts(content []byte) ([]MountPoint, error) {
 
 // SearchMountPoints finds all mount references to the source, returns a list of
 // mountpoints.
-// This function assumes source cannot be device.
+// The source can be a mount point or a normal directory (bind mount). We
+// didn't support device because there is no use case by now.
 // Some filesystems may share a source name, e.g. tmpfs. And for bind mounting,
 // it's possible to mount a non-root path of a filesystem, so we need to use
 // root path and major:minor to represent mount source uniquely.