+ #include <linux/fs.h>
+],[
+ struct file_operations file;
+
+ file.sendfile = NULL;
+], [
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_KERNEL_SENDFILE, 1,
+ [kernel has .sendfile])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.23 extract nfs export related data into exportfs.h
+AC_DEFUN([LC_HAVE_EXPORTFS_H],
+[LB_CHECK_FILE([$LINUX/include/linux/exportfs.h], [
+ AC_DEFINE(HAVE_LINUX_EXPORTFS_H, 1,
+ [kernel has include/exportfs.h])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.23 has new page fault handling API
+AC_DEFUN([LC_VM_OP_FAULT],
+[AC_MSG_CHECKING([kernel has .fault in vm_operation_struct])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/mm.h>
+],[
+ struct vm_operations_struct op;
+
+ op.fault = NULL;
+], [
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_VM_OP_FAULT, 1,
+ [kernel has .fault in vm_operation_struct])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.23 add code to wait other users to complete before removing procfs entry
+AC_DEFUN([LC_PROCFS_USERS],
+[AC_MSG_CHECKING([if kernel has pde_users member in procfs entry struct])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/proc_fs.h>
+],[
+ struct proc_dir_entry pde;
+
+ pde.pde_users = 0;
+],[
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_PROCFS_USERS, 1,
+ [kernel has pde_users member in procfs entry struct])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.23 exports exportfs_decode_fh
+AC_DEFUN([LC_EXPORTFS_DECODE_FH],
+[LB_CHECK_SYMBOL_EXPORT([exportfs_decode_fh],
+[fs/exportfs/expfs.c],[
+ AC_DEFINE(HAVE_EXPORTFS_DECODE_FH, 1,
+ [exportfs_decode_fh has been export])
+],[
+])
+])
+
+# 2.6.24
+
+# 2.6.24 need linux/mm_types.h included
+AC_DEFUN([LC_HAVE_MMTYPES_H],
+[LB_CHECK_FILE([$LINUX/include/linux/mm_types.h], [
+ AC_DEFINE(HAVE_LINUX_MMTYPES_H, 1,
+ [kernel has include/mm_types.h])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.24 has bio_endio with 2 args
+AC_DEFUN([LC_BIO_ENDIO_2ARG],
+[AC_MSG_CHECKING([if kernel has bio_endio with 2 args])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/bio.h>
+],[
+ bio_endio(NULL, 0);
+], [
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_BIO_ENDIO_2ARG, 1,
+ [kernel has bio_endio with 2 args])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.24 has new members in exports struct.
+AC_DEFUN([LC_FH_TO_DENTRY],
+[AC_MSG_CHECKING([if kernel has .fh_to_dentry member in export_operations struct])
+LB_LINUX_TRY_COMPILE([
+#ifdef HAVE_LINUX_EXPORTFS_H
+ #include <linux/exportfs.h>
+#else
+ #include <linux/fs.h>
+#endif
+],[
+ struct export_operations exp;
+
+ exp.fh_to_dentry = NULL;
+], [
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_FH_TO_DENTRY, 1,
+ [kernel has .fh_to_dentry member in export_operations struct])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.24 removes long aged procfs entry -> deleted member
+AC_DEFUN([LC_PROCFS_DELETED],
+[AC_MSG_CHECKING([if kernel has deleted member in procfs entry struct])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/proc_fs.h>
+],[
+ struct proc_dir_entry pde;
+
+ pde.deleted = NULL;
+], [
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_PROCFS_DELETED, 1,
+ [kernel has deleted member in procfs entry struct])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.24 has bdi_init()/bdi_destroy() functions.
+AC_DEFUN([LC_EXPORT_BDI_INIT],
+[LB_CHECK_SYMBOL_EXPORT([bdi_init],
+[mm/backing-dev.c],[
+ AC_DEFINE(HAVE_BDI_INIT, 1,
+ [bdi_init/bdi_destroy functions are present])
+],[
+])
+])
+
+# 2.6.25
+
+# 2.6.25 change define to inline
+AC_DEFUN([LC_MAPPING_CAP_WRITEBACK_DIRTY],
+[AC_MSG_CHECKING([if kernel have mapping_cap_writeback_dirty])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/backing-dev.h>
+],[
+ #ifndef mapping_cap_writeback_dirty
+ mapping_cap_writeback_dirty(NULL);
+ #endif
+],[
+ AC_MSG_RESULT([yes])
+ AC_DEFINE(HAVE_MAPPING_CAP_WRITEBACK_DIRTY, 1,
+ [kernel have mapping_cap_writeback_dirty])
+],[
+ AC_MSG_RESULT([no])
+])
+])
+
+# 2.6.26
+
+# 2.6.26 isn't export set_fs_pwd and change paramter in fs struct
+AC_DEFUN([LC_FS_STRUCT_USE_PATH],
+[AC_MSG_CHECKING([fs_struct use path structure])
+LB_LINUX_TRY_COMPILE([
+ #include <asm/atomic.h>
+ #include <linux/spinlock.h>
+ #include <linux/fs_struct.h>