Linux 4.1 compat: configure bdi_setup_and_register()

Pull struct backing_dev_info off the stack: by linux-4.1 it's grown
past our 1024 byte stack frame warning limit resulting in an incorrect
configure result.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Closes #3671

diff --git a/config/kernel-bdi-setup-and-register.m4 b/config/kernel-bdi-setup-and-register.m4
index 11eefb28bfcaf4b7b39e67c69ed9d1b2b37d0f49..d1062e17ec1e2d922a591b7cb41d99b813af8524 100644 (file)
--- a/config/kernel-bdi-setup-and-register.m4
+++ b/config/kernel-bdi-setup-and-register.m4
@@ -7,8 +7,8 @@ AC_DEFUN([ZFS_AC_KERNEL_BDI_SETUP_AND_REGISTER], [
        AC_MSG_CHECKING([whether bdi_setup_and_register() wants 2 args])
        ZFS_LINUX_TRY_COMPILE_SYMBOL([
                #include <linux/backing-dev.h>
-       ], [
                struct backing_dev_info bdi;
+       ], [
                char *name = "bdi";
                int error __attribute__((unused)) =
                    bdi_setup_and_register(&bdi, name);
@@ -21,8 +21,8 @@ AC_DEFUN([ZFS_AC_KERNEL_BDI_SETUP_AND_REGISTER], [
                AC_MSG_CHECKING([whether bdi_setup_and_register() wants 3 args])
                ZFS_LINUX_TRY_COMPILE_SYMBOL([
                        #include <linux/backing-dev.h>
-               ], [
                        struct backing_dev_info bdi;
+               ], [
                        char *name = "bdi";
                        unsigned int cap = BDI_CAP_MAP_COPY;
                        int error __attribute__((unused)) =