[Ocfs2-devel] [patch 2/5] ocfs2: add compatibility for mandatory_lock()

[Jeff Mahoney]

 SLES10 doesn't have a mandatory_lock() function, but does support
 IS_MANDATORY() and the associated functions.

 This patch adds mandatory_lock() support.

Signed-off-by: Jeff Mahoney <jeffm at suse.com>
---

 Config.make.in                       |    1 +
 configure.in                         |    6 ++++++
 fs/ocfs2/Makefile                    |    4 ++++
 kapi-compat/include/mandatory_lock.h |   27 +++++++++++++++++++++++++++
 4 files changed, 38 insertions(+)

--- a/Config.make.in	2008-01-31 13:48:44.000000000 -0500
+++ b/Config.make.in	2008-01-31 13:49:00.000000000 -0500
@@ -88,6 +88,7 @@ INVALIDATEPAGE_RETURNS_INT = @INVALIDATE
 DIO_OLD_GET_BLOCKS = @DIO_OLD_GET_BLOCKS@
 HAS_SYSTEM_UTSNAME = @HAS_SYSTEM_UTSNAME@
 NO_LOCKDEP = @NO_LOCKDEP@
+NO_MANDATORY_LOCK = @NO_MANDATORY_LOCK@
 
 OCFS_DEBUG = @OCFS_DEBUG@
 
--- a/configure.in	2008-01-31 13:48:44.000000000 -0500
+++ b/configure.in	2008-01-31 13:49:00.000000000 -0500
@@ -384,6 +384,12 @@ OCFS2_CHECK_KERNEL([linux/lockdep.h], lo
   NO_LOCKDEP=yes, [^struct lock_class {])
 AC_SUBST(NO_LOCKDEP)
 
+NO_MANDATORY_LOCK=
+OCFS2_CHECK_KERNEL([mandatory_lock() in fs.h], fs.h, ,
+  NO_MANDATORY_LOCK=yes, [^static inline int mandatory_lock(])
+AC_SUBST(NO_MANDATORY_LOCK)
+KAPI_COMPAT_HEADERS="$KAPI_COMPAT_HEADERS mandatory_lock.h"
+
 # using -include has two advantages:
 #  the source doesn't need to know to include compat headers
 #  the compat header file names don't go through the search path
--- a/fs/ocfs2/Makefile	2008-01-31 13:48:44.000000000 -0500
+++ b/fs/ocfs2/Makefile	2008-01-31 13:49:00.000000000 -0500
@@ -140,6 +140,10 @@ ifdef NO_LOCKDEP
 EXTRA_CFLAGS += -DNO_LOCKDEP
 endif
 
+ifdef NO_MANDATORY_LOCK
+EXTRA_CFLAGS += -DNO_MANDATORY_LOCK
+endif
+
 #
 # Since SUBDIRS means something to kbuild, define them safely.  Do not
 # include trailing slashes.
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ b/kapi-compat/include/mandatory_lock.h	2008-01-31 13:49:00.000000000 -0500
@@ -0,0 +1,27 @@
+#ifndef KAPI_MANDATORY_LOCK_H
+#define KAPI_MANDATORY_LOCK_H
+
+#ifdef NO_MANDATORY_LOCK
+#include <linux/fs.h>
+/*
+ * Candidates for mandatory locking have the setgid bit set
+ * but no group execute bit -  an otherwise meaningless combination.
+ */
+
+static inline int __mandatory_lock(struct inode *ino)
+{
+        return (ino->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID;
+}
+
+/*
+ * ... and these candidates should be on MS_MANDLOCK mounted fs,
+ * otherwise these will be advisory locks
+ */
+
+static inline int mandatory_lock(struct inode *ino)
+{
+        return IS_MANDLOCK(ino) && __mandatory_lock(ino);
+}
+#endif
+
+#endif /* KAPI_MANDATORY_LOCK_H */