X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=lib%2Flibspl%2Finclude%2Fsys%2Fmount.h;h=145e785e3d520acf33db9b2fb9dbbbc0beb361c2;hb=756c3e5a9ce36461939a8dc421918e1c3a379fa6;hp=f6a67c6a0caf2c106d8118e0cdb7b1bbf09ea983;hpb=3fb1fcdea167d705e050a0383ec61b95fbe8a0ed;p=zfs.git

diff --git a/lib/libspl/include/sys/mount.h b/lib/libspl/include/sys/mount.h
index f6a67c6..145e785 100644
--- a/lib/libspl/include/sys/mount.h
+++ b/lib/libspl/include/sys/mount.h
@@ -42,11 +42,42 @@
 #define BLKGETSIZE64		_IOR(0x12, 114, size_t)
 #endif
 
+/*
+ * Some old glibc headers don't correctly define MS_DIRSYNC and
+ * instead use the enum name S_WRITE.  When using these older
+ * headers define MS_DIRSYNC to be S_WRITE.
+ */
+#if !defined(MS_DIRSYNC)
+#define MS_DIRSYNC		S_WRITE
+#endif
+
 #define	MS_USERS	0x40000000
 #define	MS_OWNER	0x10000000
 #define	MS_GROUP	0x08000000
 #define	MS_COMMENT	0x02000000
-#define	MS_FORCE	MNT_FORCE
-#define	MS_DETACH	MNT_DETACH
+
+/*
+ * Older glibc <sys/mount.h> headers did not define all the available
+ * umount2(2) flags.  Both MNT_FORCE and MNT_DETACH are supported in the
+ * kernel back to 2.4.11 so we define them correctly if they are missing.
+ */
+#ifdef MNT_FORCE
+# define MS_FORCE	MNT_FORCE
+#else
+# define MS_FORCE	0x00000001
+#endif /* MNT_FORCE */
+
+#ifdef MNT_DETACH
+# define MS_DETACH	MNT_DETACH
+#else
+# define MS_DETACH	0x00000002
+#endif /* MNT_DETACH */
+
+/*
+ * Overlay mount is default in Linux, but for solaris/zfs
+ * compatibility, MS_OVERLAY is defined to explicitly have the user
+ * provide a flag (-O) to mount over a non empty directory.
+ */
+#define MS_OVERLAY      0x00000004
 
 #endif /* _LIBSPL_SYS_MOUNT_H */