QStorageInfo: Add support for obtaining subvolume names

[ChangeLog][QtCore][QStorageInfo] Added QStorageInfo::subvolume(), which
returns the name of the subvolume of a volume that was mounted, if one
was detected. This is currently implemented only for btrfs on Linux.

Change-Id: Ib57b52598e2f452985e9fffd1459f3145d733ce5
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/corelib/io/qstorageinfo_p.h b/src/corelib/io/qstorageinfo_p.h
index a14fa8480a..ec5bb785e3 100644
--- a/src/corelib/io/qstorageinfo_p.h
+++ b/src/corelib/io/qstorageinfo_p.h
@@ -85,6 +85,7 @@ protected:
 public:
     QString rootPath;
     QByteArray device;
+    QByteArray subvolume;
     QByteArray fileSystemType;
     QString name;