util: Add is_anon_inode helper

Will need it for eventpoll/eventfd/inotify.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

include/util.h

@@ -11,6 +11,7 @@
 #include <errno.h>
 
 #include <sys/types.h>
+#include <sys/statfs.h>
 #include <dirent.h>
 
 #include "compiler.h"
@@ -276,5 +277,6 @@ static inline dev_t kdev_to_odev(u32 kdev)
 }
 
 int copy_file(int fd_in, int fd_out, size_t bytes);
+bool is_anon_inode(struct statfs *statfs);
 
 #endif /* UTIL_H_ */

util.c

@@ -301,3 +301,12 @@ int copy_file(int fd_in, int fd_out, size_t bytes)
 
 	return 0;
 }
+
+#ifndef ANON_INODE_FS_MAGIC
+# define ANON_INODE_FS_MAGIC 0x09041934
+#endif
+
+bool is_anon_inode(struct statfs *statfs)
+{
+	return statfs->f_type == ANON_INODE_FS_MAGIC;
+}