--- old/src/hotspot/os_cpu/linux_x86/gc/z/zBackingFile_linux_x86.hpp	2019-05-02 09:57:42.955832570 +0200
+++ new/src/hotspot/os_cpu/linux_x86/gc/z/zBackingFile_linux_x86.hpp	2019-05-02 09:57:42.709824445 +0200
@@ -26,12 +26,14 @@
 
 #include "memory/allocation.hpp"
 
+class ZErrno;
+
 class ZBackingFile {
 private:
-  static bool _hugetlbfs_mmap_retry;
-
   int      _fd;
+  size_t   _size;
   uint64_t _filesystem;
+  size_t   _block_size;
   size_t   _available;
   bool     _initialized;
 
@@ -43,11 +45,17 @@
   bool is_hugetlbfs() const;
   bool tmpfs_supports_transparent_huge_pages() const;
 
-  bool try_split_and_expand_tmpfs(size_t offset, size_t length, size_t alignment) const;
-  bool try_expand_tmpfs(size_t offset, size_t length, size_t alignment) const;
-  bool try_expand_tmpfs(size_t offset, size_t length) const;
-  bool try_expand_hugetlbfs(size_t offset, size_t length) const;
-  bool try_expand_tmpfs_or_hugetlbfs(size_t offset, size_t length, size_t alignment) const;
+  ZErrno fallocate_compat_ftruncate(size_t size) const;
+  ZErrno fallocate_compat_mmap(size_t offset, size_t length, bool reserve_only) const;
+  ZErrno fallocate_compat_pwrite(size_t offset, size_t length) const;
+  ZErrno fallocate_fill_hole_compat(size_t offset, size_t length);
+  ZErrno fallocate_fill_hole_syscall(size_t offset, size_t length);
+  ZErrno fallocate_fill_hole(size_t offset, size_t length);
+  ZErrno fallocate_punch_hole(size_t offset, size_t length);
+  ZErrno split_and_fallocate(bool punch_hole, size_t offset, size_t length);
+  ZErrno fallocate(bool punch_hole, size_t offset, size_t length);
+
+  bool commit_inner(size_t offset, size_t length);
 
 public:
   ZBackingFile();
@@ -55,9 +63,11 @@
   bool is_initialized() const;
 
   int fd() const;
+  size_t size() const;
   size_t available() const;
 
-  size_t try_expand(size_t offset, size_t length, size_t alignment) const;
+  size_t commit(size_t offset, size_t length);
+  size_t uncommit(size_t offset, size_t length);
 };
 
 #endif // OS_CPU_LINUX_X86_GC_Z_ZBACKINGFILE_LINUX_X86_HPP