mirror_zfs/config/kernel-d-make-root.m4

dnl #
dnl # 3.4.0 API change
dnl # Added d_make_root() to replace previous d_alloc_root() function.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_D_MAKE_ROOT],
	[AC_MSG_CHECKING([whether d_make_root() is available])
	ZFS_LINUX_TRY_COMPILE_SYMBOL([
		#include <linux/dcache.h>
	], [
		d_make_root(NULL);
	], [d_make_root], [fs/dcache.c], [
		AC_MSG_RESULT(yes)
		AC_DEFINE(HAVE_D_MAKE_ROOT, 1, [d_make_root() is available])
	], [
		AC_MSG_RESULT(no)
	])
])
Linux 3.4 compat, d_make_root() replaces d_alloc_root() torvalds/linux@adc0e91ab142abe93f5b0d7980ada8a7676231fe introduced introduced d_make_root() as a replacement for d_alloc_root(). Further commits appear to have removed d_alloc_root() from the Linux source tree. This causes the following failure: error: implicit declaration of function 'd_alloc_root' [-Werror=implicit-function-declaration] To correct this we update the code to use the current d_make_root() interface for readability. Then we introduce an autotools check to determine if d_make_root() is available. If it isn't then we define some compatibility logic which used the older d_alloc_root() interface. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #776 2012-06-06 21:08:00 +04:00			`dnl #`
			`dnl # 3.4.0 API change`
			`dnl # Added d_make_root() to replace previous d_alloc_root() function.`
			`dnl #`
When checking for symbol exports, try compiling. This patch adds a new autoconf function: ZFS_LINUX_TRY_COMPILE_SYMBOL. This new function does the following: - Call LINUX_TRY_COMPILE with the specified parameters. - If unsuccessful, return false. - If successful and we're configuring with --enable-linux-builtin, return true. - Else, call CHECK_SYMBOL_EXPORT with the specified parameters and return the result. All calls to CHECK_SYMBOL_EXPORT are converted to LINUX_TRY_COMPILE_SYMBOL so that the tests work even when configuring for builtin on a kernel which doesn't have loadable module support, or hasn't been built yet. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #851 2012-07-26 01:38:58 +04:00			`AC_DEFUN([ZFS_AC_KERNEL_D_MAKE_ROOT],`
			`[AC_MSG_CHECKING([whether d_make_root() is available])`
			`ZFS_LINUX_TRY_COMPILE_SYMBOL([`
			`#include <linux/dcache.h>`
			`], [`
			`d_make_root(NULL);`
			`], [d_make_root], [fs/dcache.c], [`
			`AC_MSG_RESULT(yes)`
			`AC_DEFINE(HAVE_D_MAKE_ROOT, 1, [d_make_root() is available])`
			`], [`
			`AC_MSG_RESULT(no)`
			`])`
Linux 3.4 compat, d_make_root() replaces d_alloc_root() torvalds/linux@adc0e91ab142abe93f5b0d7980ada8a7676231fe introduced introduced d_make_root() as a replacement for d_alloc_root(). Further commits appear to have removed d_alloc_root() from the Linux source tree. This causes the following failure: error: implicit declaration of function 'd_alloc_root' [-Werror=implicit-function-declaration] To correct this we update the code to use the current d_make_root() interface for readability. Then we introduce an autotools check to determine if d_make_root() is available. If it isn't then we define some compatibility logic which used the older d_alloc_root() interface. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #776 2012-06-06 21:08:00 +04:00			`])`